Answer:
I believe it's C. The school has a new science lab, and plans for a new auditorium are moving ahead.
Explanation:
a complex sentence must have two or more coordinate independent clauses and one or more dependent clause. In this case, the independent clause is "the school has a new science lab", because this alone can be a sentence. The dependent clause here is "plans for a new auditorium are moving ahead", since this phrase alone cannot make a complete sentence. hope this helps!
