In which two of the following ways can the sentences in the box be correctly combined? While heading toward the beach, it began to rain heavily. We decided to turn back.

While heading toward the beach, it began to rain heavily, we decided to turn back.
While heading toward the beach, it began to rain heavily; we decided to turn back.
Because we decided to turn back while heading toward the beach, it began to rain heavily.
While heading toward the beach, we decided to turn back because it began to rain heavily.
Because it began to rain heavily, while heading toward the beach, we decided to turn back.