Question

complete the statement below. a hypothesis must be...
a question.
always correct.
testable.

Explanation:

A hypothesis is a proposed explanation in scientific inquiry. It is not a question (so the first option is wrong) and doesn't have to be always correct (as it's tested and can be rejected, so the second option is wrong). A key characteristic of a hypothesis is that it must be testable, meaning it can be investigated through experiments or observations.

Answer:

C. testable.