Idioms and Phrases - Verbal and Reasoning

In the following questions four alternatives are given for the idiom/phraseitalicised and underlinedin the sentence. Choose the alternative which best expresses the meaning of idiom/phrase.
Q1:

Discipline is on the wane in schools and colleges these days.

A declining

B increasing

C spreading

D spiralling

ANS:A - declining

No answer description is available.