Final answer:
A proposition is a declarative sentence capable of being true or false, often tied to a fact or an opinion that can be verified. It can also be part of a hypothesis, which is similar to a suggestion for further investigation. The correct answer is option C.
Step-by-step explanation:
The term proposition refers to a declarative sentence that makes a claim which can be determined to be either true or false. A proposition is not just any statement but one that asserts a fact or an opinion and is subject to verification or falsification. For example, the statement 'Dogs are mammals' is a proposition because it is a claim that can be tested and shown to be true.
In the context of the options provided, 'A simple statement of fact' closely defines a proposition. However, in philosophy and logic, the term can be used more broadly to include any declarative sentence that expresses a truth claim, regardless of whether the truth of the claim is known. Furthermore, a proposition can be part of a hypothesis, which is an assumption made for the sake of argument or investigation.
Answering the separate question of which word is closest to the same meaning as hypothesis, the best choice would be 'suggestion' (d). A hypothesis is a proposed explanation made on the basis of limited evidence as a starting point for further investigation, which aligns with the idea of a suggestion rather than a confirmed fact, law, formula, or conclusion. The correct answer is option C.