An explanation is one that gives a reason for something. The sentence that features an introductory phrase that explains why the main action happened is;
- (4) Because she took her eyes off the road to answer the phone call, Jayla lost control of her car and crashed through the front of Kayla's house.
In this introduction, we see that the speaker explains the reason why an accident occurred.
Jayla had an accident because she took her eyes off the road while answering her phone call. This statement is explanatory because it shows why an event occurred.
Thus, sentence 4 explains why the main action happened.
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