Out of all the alternatives given, select the option which closely fits the given idiom/phrase.
Bite off more than you can chew

Correct option is A

Option (a) is the correct meaning of the given idiom.
Idiom Meaning:
Bite off more than you can chew means to take on more responsibility or work than you can manage. (अपनी क्षमता से अधिक काम लेना)
Example: By agreeing to lead five projects at once, he has bitten off more than he can chew.
Other related idioms and their meanings:
Burning the candle at both ends – Overworking oneself
In over your head – Being involved in something too difficult
Spread too thin – Trying to do too many things at once