Dear sureshlasi, some of the questions are given wrong answers or options. as earlier waqasishtiaq has pointed out about the neil armstrong.
The one which i have pointed out is,

#6
14. Which of the following semi-conductor ?

a. Copper
b. Zirconium
c. Silver
d. Germanium
and check it answer is given as option 'a'.

Copper is a pure conductor, not a semi-conductor. the right answer is 'd'. because all the elements of group 4A are known as semi-conductor.

Beside this question, there are also other questions which needs to be pointed out because the concepts of students will get wrong or they will acquire wrong information.

So, it is requested to please take care of the answers...........
Thanks