Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.
I left the office. There was a power cut just then.
A.I left the office after there was a power cut.
B.Hardly I had left the office when there was a power cut.
C.No sooner had I left the office than there was a power cut.
D.I left the office long before there was a power cut.