The answer to your question would be that the combined sentence uses a compound verb. That is, the correct option would be C.
In the sentence above, the subject of the sentence is the personal pronoun "They" and the predicate is the verbal predicate "had their equipment packed and were off!". The object taken by the verb is the NP "their equipment packed and survived". Taken all this into account, the sentence uses a compound verb (packed and were off).
