The correct option is B. veer.
In this sentence, "veer" is the simple predicate. A simple predicate is the main verb that in the predicate, which generally tells what the subject is doing. In this case, the main verb ("veer") is referring to an activity of "hurricanes", the subject of the sentence. Moreover, this is a complex sentence since it includes an independent clause ("Hurricanes sometimes veer off course") and a dependent clause ("Although meteorologist work hard to predict hurricanes’ paths"), which cannot stand by itself as the independent clause. The simple predicate is part of the independent clause.