Which sentence has a verb error?

AIf you want to see a good movie, then don't go see Flicker.
BIf I were the President of the US, I'd make education my first priority.
CIf I was going on a trip, I'd probably visit Europe instead of South America.
DI wasn't sure whether or not the old man was bad at chess or just fooling me.

Verified Answer :

The answer is C because The sentence with a verb error is the following one: If I was going on a trip, I'd probably visit Europe instead of South America. The sentence should read as follows: "If I were going on a trip, I'd probably visit Europe instead of South America."

Answer:

c. If I was going on a trip, I'd probably visit Europe instead of South America.

Explanation:

This is the answer that is on the test