Correct option is A
A conjecture is a statement that is believed to be true, but has not yet been proven. The statement "1 less than or 1 more than a multiple of 6 are prime numbers" is a conjecture because it has not been formally proven to be true. However, there is evidence to support the conjecture, such as the fact that the first 17 prime numbers can be written in the form 6n-1 or 6n+1.
An axiom is a statement that is assumed to be true without proof. A theorem is a statement that has been proven to be true using logic and reasoning. A generalization is a statement that applies to more than one specific case.