1 : He had started the book thinking
P : he had decided
Q : that it would be an interesting work,
R : but by the time
S : he reached the middle
6 : throw it into the bin.

The proper sequence should be:

A. PSQR

B. QRSP

C. RSPQ

D. SPRQ

Answer: Option B

Solution(By Examveda Team)

He had started the book thinking that it would be an interesting work, but by the time he reached the middle he had decided throw it into the bin.