{"id":183425,"date":"2025-01-16T12:49:31","date_gmt":"2025-01-16T12:49:31","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=183425"},"modified":"2025-01-16T12:49:33","modified_gmt":"2025-01-16T12:49:33","slug":"which-of-the-following-is-a-legal-identifier","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/01\/16\/which-of-the-following-is-a-legal-identifier\/","title":{"rendered":"Which of the following is a legal identifier"},"content":{"rendered":"\n<p>Which of the following is a legal identifier? <\/p>\n\n\n\n<p>a. 1program <\/p>\n\n\n\n<p>Obiprogram!<\/p>\n\n\n\n<p> c.program 1 <\/p>\n\n\n\n<p>d.program_1<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>The correct answer is <strong>d. program_1<\/strong>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation:<\/h3>\n\n\n\n<p>In programming, an <strong>identifier<\/strong> is the name used to identify variables, functions, or other user-defined elements in a program. Each programming language has its specific rules for what constitutes a valid identifier. However, most modern programming languages share common guidelines for identifiers:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>The first character<\/strong> must be a letter (a-z, A-Z) or an underscore (<code>_<\/code>). It cannot be a digit.<\/li>\n\n\n\n<li>Subsequent characters can include letters, digits (0-9), and underscores.<\/li>\n\n\n\n<li>Identifiers cannot include spaces, special characters like <code>!<\/code>, <code>@<\/code>, or <code>#<\/code>.<\/li>\n\n\n\n<li>Identifiers cannot be reserved keywords or language-specific words (like <code>if<\/code>, <code>while<\/code>, <code>class<\/code>, etc.).<\/li>\n\n\n\n<li>Some languages may enforce case sensitivity (e.g., <code>Program<\/code> and <code>program<\/code> are different in Python).<\/li>\n<\/ol>\n\n\n\n<h4 class=\"wp-block-heading\">Now, analyzing each option:<\/h4>\n\n\n\n<p><strong>a. <code>1program<\/code><\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>This is <strong>not a legal identifier<\/strong> because it starts with a digit, which violates the rule that the first character must be a letter or underscore.<\/li>\n<\/ul>\n\n\n\n<p><strong>b. <code>Obiprogram!<\/code><\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>This is <strong>not a legal identifier<\/strong> because it contains a special character (<code>!<\/code>), which is not allowed in identifiers.<\/li>\n<\/ul>\n\n\n\n<p><strong>c. <code>program 1<\/code><\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>This is <strong>not a legal identifier<\/strong> because it contains a space. Identifiers must not have spaces.<\/li>\n<\/ul>\n\n\n\n<p><strong>d. <code>program_1<\/code><\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>This is <strong>a legal identifier<\/strong> because it starts with a letter (<code>p<\/code>), includes only valid characters (letters, digits, and an underscore), and does not contain spaces or special characters.<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">Why <code>program_1<\/code> is valid:<\/h4>\n\n\n\n<p>Identifiers like <code>program_1<\/code> adhere to the naming conventions of most programming languages. The use of underscores makes it readable, and the combination of letters and digits ensures it is descriptive. It\u2019s a common practice to use underscores to separate words in identifiers, especially when spaces are disallowed.<\/p>\n\n\n\n<p>Thus, <strong><code>program_1<\/code><\/strong> is the only valid identifier among the options provided.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Which of the following is a legal identifier? a. 1program Obiprogram! c.program 1 d.program_1 The Correct Answer and Explanation is : The correct answer is d. program_1. Explanation: In programming, an identifier is the name used to identify variables, functions, or other user-defined elements in a program. Each programming language has its specific rules for [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-183425","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/183425","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=183425"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/183425\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=183425"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=183425"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=183425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}