Which type of sign tells you what you must not do?

The correct answer and explanation is:
The correct answer is prohibition signs.
Prohibition signs are designed to inform individuals of actions they must not take. These signs are typically used in environments such as workplaces, public spaces, and roads to prevent dangerous behaviors or activities. The primary characteristic of these signs is that they include a symbol or a clear instruction combined with a red circle with a diagonal line through it, indicating that the action is forbidden.
In general, prohibition signs communicate an immediate danger or a rule that must be strictly followed for safety, legal, or health reasons. For example, “No Smoking” signs in hospitals and other public places or “Do Not Enter” signs on roads are common types of prohibition signs. These signs help to minimize risks by clearly stating actions that could cause harm or disrupt the order.
The purpose of prohibition signs is to provide clear, visible instructions that are easily understood. The use of red, which universally signifies danger or warning, ensures that these signs are noticed and followed. The prohibitive message helps prevent accidents, ensures compliance with safety regulations, and maintains the wellbeing of individuals in the area.
In addition to the visual elements, some prohibition signs also include text for clarification. The combination of symbols and words helps overcome language barriers, ensuring that everyone, regardless of their language or background, understands the message. This is especially important in places with diverse populations or for international travelers.
Overall, prohibition signs are crucial for maintaining safety and order in various settings, preventing actions that could lead to harm, legal issues, or accidents.