Correct Answer: happy

Solution : The correct choice is the second option.

Explanation : In the context of the sentence, "The party was a happy hour for everyone, except Mukesh," it implies that everyone enjoyed the party except Mukesh. Using happy here denotes that the party brought joy or pleasure to the attendees, contrasting Mukesh's experience with the general positive atmosphere of the event.
The meanings of the other options are as follows:

• Welcome means to be received with pleasure or delight.
• Dry means without interest or enjoyment; dull or uninteresting.
• Stable means firm, steady, or unchanging.

Therefore, the complete sentence would be: "The party was a happy hour for everyone, except Mukesh."