Correct Answer: eager

Solution : The correct option is the third option.

Explanation:
" Eager " means feeling keen interest, enthusiasm, or anticipation, which aligns closely with the context of the sentence in which someone is being asked not to display excessive excitement.

The meanings of the other options are as follows:

• Casual means relaxed, informal, not formal or serious.
• Composed means calm, collected, and showing control over emotions.
• Tired means exhausted, fatigued, or lacking energy.

Therefore, the correct answer is eager.