Answer:
The incorrect subject-verb agreement is highlighted below:
Jenna's favorite hiking trail wind from the base of Mt Diablo up to the summit which offers breathtaking views of the surrounding area.
Step-by-step explanation:
The verb that refers to a certain subject must agree with that subject. In other words, the verb must be properly conjugated according to the kind of subject we have. In this case, the main word of the subject is "trail", which is a third-person singular subject. However, the verb following it is "wind", which is not in its third-person singular form. To correct it, we must add -s to the ending of the verb:
Jenna's favorite hiking trail winds from the base of Mt Diablo up to the summit which offers breathtaking views of the surrounding area.