Which of the following is a compound sentence?
A.
I don’t like to run or swim
B.
He ran, but she ran faster
C.
He will not run today
D.
Swimming is extremely fun

A compound sentence consists of two or more independent clauses joined by a conjunction (like “and,” “but,” “or”) or a semicolon.
Let’s evaluate each option:
A. I don’t like to run or swim
- This is a simple sentence with a compound predicate (“run” and “swim”).
B. He ran, but she ran faster
- This is a compound sentence. It has two independent clauses: “He ran” and “she ran faster,” connected by the conjunction “but.”
C. He will not run today
- This is a simple sentence with a single independent clause.
D. Swimming is extremely fun
- This is a simple sentence with a single independent clause.
Therefore, the compound sentence among the options is:
B. He ran, but she ran faster