What is the most appropriate meaning of the idiom?

Laugh in one’s sleeves

The correct answer is “To laugh quietly to oneself”.

Key Points

• The idiom "to laugh in one's sleeves" means to laugh quietly to oneself without anyone else knowing. 
• It is often used to describe someone who is trying to hide their amusement or pleasure.
• The phrase "in one's sleeves" refers to the fact that someone who is laughing in this way will often cover their mouth with their hand or sleeve.
• This idiom is often used in a humorous way to describe someone who is trying to keep a secret from someone else.

Hence, the correct answer is 'Option 1'