The most active ingredient in bleaching powder is-
Correct Answer : b ) Calcium hypochloriteExplanation :
Calcium hypochlorite is an inorganic compound with the formula Ca(OCl)2. It is the main active ingredient of commercial products like bleaching powder, chlorine powder, or chlorinated lime, which are used for water treatment and as a bleaching agent.
This compound has more available chlorine than sodium hypochlorite and is relatively stable.
Hence, (b) is the correct answer.