A conjecture in mathematics is :

The correct answer is: a proposition or conclusion that is assumed to be true on a tentative basis without proof.

Explanation:

In mathematics, a conjecture is an unproven statement, proposition, or conclusion that appears to be true based on preliminary observations, patterns, or intuition, but has not yet been rigorously proved or disproved.

Once a conjecture is formally proved using logical deduction and established axioms, it becomes a theorem. Until then, it remains a tentative statement accepted as a hypothesis subject to further proof.