Belying his mother’s worries, Rajesh’s behaviour throughout the function was . . . . . . .

The correct answer is: B. impeccable

Impeccable means “flawless” or “without fault.” In this case, Rajesh’s mother was worried that he would misbehave at the function, but he behaved perfectly.

The other options are incorrect for the following reasons:

• Immodest means “not modest” or “disrespectful.” This does not describe Rajesh’s behavior.
• Imaginable means “able to be imagined.” This does not describe Rajesh’s behavior.
• Imperial means “of or relating to an emperor.” This does not describe Rajesh’s behavior.
• Impervious means “not affected by something.” This does not describe Rajesh’s behavior.