What does a chemical symbol consist of?

A chemical symbol is a standardized notation used to represent an element. It typically consists of one letter that is always capitalized or a combination of one capital letter followed by a lowercase letter. This system ensures that each element has a unique and universally recognized representation. For example, the chemical symbol for carbon is "C," while that for aluminum is "Al."

This format allows for a clear and concise identification of elements in chemical formulas and equations. The use of both a capital and lowercase letter ensures clarity and prevents confusion with other elements, maintaining a systematic approach in the scientific community. Therefore, the correct structure is indeed a capital letter followed by a lowercase letter, affirming the choice selected.