Choose the word closest in meaning to the underlined word.

Why did you make that flippant remark about her choice of clothes?

disrespectful

The correct answer is Option (2) - disrespectful

Flippant suggests a careless or disrespectful remark, often made without considering the feelings of others.  Disrespectful directly conveys the idea of lacking respect for someone or something.

Sarcastic: This implies using irony or scorn in a way that can be hurtful, but it doesn't mean disrespectful.
Casual: This means laid-back or informal, and doesn't convey a negative connotation.
Indifferent: This means not interested or concerned, which doesn't capture the lack of respect implied by "flippant."