Questions

Hierarchy is a system of ranking in which members of a particular society are ranked in an ascending order depending on various factors.

Hence, the term hierarchy refers to a power structure in which each member knows his or her own place.

A restrictive clause is one that limits the meaning of the word it describes.

For example :: 

The girl who lives next door is beautiful.

This restrictive clause limits "the girl" to say it's specifically the one next door.

Before transferring the fish, the position is the man with the fish and the bucket of water. After transferring the position is : the man without the fish, but the fish inside the water in the bucket. Thus to know whether there is any change in weight, it is enough to consider whether there is any change in weight when the fish in air is transferred into the water. The answer is there is no change as when in water though it loses weight due to upthrust of water on it, the level of water increases and exerts an equal force at the bottom

The centripetal force having  been removed the body cannot execute the curved path. (B) is Correct.