wow.. what a question of reasoning

There are 100 questions in a two hour M.C.A. entrance test. Among these questions, 40 will be in the area of Reasoning. It is suggested that two and a half times as much time be allowed for each reasoning problem as for each of the other questions. How many minutes should be spent on the Reasoning Problem?

|| |UPAC discussion OF previous year question & assertion reason OF iupac ||

|| isomerism || discussion OF previous year question || assertion reason OF isomerism ||

Observe the following diagram and answer the questions. What are the possible reasons for this eye defect ?