Select the most appropriate option that can substitute the highlighted segment in the given sentence.
Brian remained silent during the board meeting, though Rahul was unaware that he had an ace up his sheath the entire time.

Correct option is A

The correct substitution of the highlighted words is (a) an ace up his sleeve.
Explanation: The idiom “an ace up his sleeve” means having a hidden advantage or secret plan that can be used when needed.

The given phrase “an ace up his sheath” is incorrect and non-idiomatic.

“Sleeve” is the correct term used in this common English idiom.
Example: The lawyer appeared calm during the argument because he had an ace up his sleeve for the final round of questioning.

Other related idioms:

1. Play your cards close to your chest

Meaning: To keep your plans, ideas, or thoughts secret from others.

2. Have a trick up your sleeve

Meaning: To have a secret or surprise strategy or resource that can be used when needed.

3. Keep something under wraps

Meaning: To keep something secret until the right time.

4. Hold all the cards

Meaning: To be in a strong or advantageous position in a situation.