Which sentence shows correct subject-verb agreement?

A.

There're a good answer to that question.

B.

There's a good answer to that question.

B would be the correct answer.

B is the answer

To find this answer you should remember that the words there're and there's are contractions which means they are two words squished together. now which sentence makes more sense to you?

A. There are a good answer to that question

or

B. There is a good answer to that question