The Correct Answer and Explanation is:
Based on the context of the sentence, the correct words are matter and mixtures.
The completed sentence should read:
“Most of the matter people encounter in everyday life consists of mixtures of different substances.”
Explanation
This sentence describes a fundamental concept in chemistry and physical science. The choice of the words “matter” and “mixtures” is based on both scientific accuracy and grammatical structure.
The first missing word is matter. In a scientific context, “matter” refers to any substance that has mass and takes up space by having volume. This encompasses everything we see, touch, and interact with in our daily lives, from the air we breathe to the food we eat and the objects we use. The use of the singular verb “consists” after the phrase “most of the…” is a key grammatical clue. This structure is correct when the noun that follows is a non-count or mass noun, like “matter.” If the word were a plural count noun such as “materials,” the verb would need to be plural (“consist”), making “matter” the grammatically superior choice for the provided sentence.
The second missing word is mixtures. The phrase “consists of… of different substances” clearly indicates that the subject is a composition of multiple components. A “mixture” is defined as a substance made by combining two or more different materials in such a way that no chemical reaction occurs. Most things we encounter are not pure substances but are instead mixtures. For example, air is a mixture of nitrogen, oxygen, and other gases; salt water is a mixture of salt and water; and alloys like steel are mixtures of iron and carbon. Therefore, “mixtures” is the precise scientific term to complete the thought, accurately stating that everyday matter is typically composed of various combined substances.
The word “choose” in the original image appears to be an error from an optical character recognition (OCR) scan and does not fit the context of the sentence.
