Correct Answer: B
Explanation:
Meaning: Indecorous behavior means behavior which isn't proper or socially acceptable.
Indecorous means lacking decorum, propriety or good taste etc.
Example: Indecorous behavior will not be tolerated in our school.
Synonyms: Improper, Indecent, Rude, Uncouth, Vulgar
Antonyms: Befitting, Apt, Opportune, Proper