Once he had finished taking his exams, he hurried home

Once he had finished taking his exams, he hurried home to prepare for his friend’s surprise birthday party.

a) Once he had finished taking his exams, he hurried home
b) Running home after Eric finished his exams he had
c) Upon completing his exams, Eric hurried home
d) After finishing Eric’s exams, he ran home
e) Eric quickly ran home upon he completed his exams


The official answer is C.
Why A is not the correct answer

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