Sentence Improvement - Verbal and Reasoning

Directions to SolveIn questions given below, a part of the sentence isitalicised and underlined. Below are given alternatives to the italicised part which may improve the sentence. Choose the correct alternative. In case no improvement is needed, option 'D' is the answer.
Q1:

hoping not to be disturbed, I sat down in my easy chair to read the book. I won as a prize.

A I had won as a prize

B I have won as prize

C I had to win as a prize

D No improvement

ANS:A - I had won as a prize

No answer description is available.