Which one of the following is a run-on sentence?

A. I would talk to Frank if I knew him, but people don’t ever talk to him.

B. I think Frank might be too busy he likes to make people think he’s smart.

C. Jerry told me he likes June, but Hank likes Julie better.

D. I’m not a fan of wrestling, but Lie is.

I think the answer is "B"

Thank you

I think Frank might be too busy. He likes to make people think he’s smart.

The correct answer is indeed option "B". It is a run-on sentence because it contains two independent clauses that are not properly joined or separated. A run-on sentence occurs when two or more independent clauses are joined without the necessary punctuation or coordinating conjunction.

In option "B", the independent clauses are: "I think Frank might be too busy" and "he likes to make people think he’s smart." These clauses are not properly joined or separated, making it a run-on sentence.

To correct this run-on sentence, you can use a coordinating conjunction (such as "but") to connect the two independent clauses: "I think Frank might be too busy, but he likes to make people think he’s smart."

Right.

The answer is B, because all your other sentences use a conjunction to connect the independent clauses that could be sentences, but B doesn't do that. It just goes on without a conjunction or punctuation to make it into another sentence.