Explanation:

- Trepidation: This word means a feeling of fear or anxiety about something that may happen. It's often associated with apprehension or nervousness.

- Option 1 - Disastrous: This word means causing great damage or harm. It doesn't align with the meaning of trepidation, as it describes an event or outcome, not a feeling.

- Option 2 - Exaggerate: This verb means to represent something as being larger, better, or worse than it really is. It doesn't share a similar meaning with trepidation.

- Option 3 - Nervousness: This word means the state of being anxious or apprehensive. It closely matches the meaning of trepidation, which also involves a sense of anxiety or fear.

- Option 4 - Ephemeral: This adjective describes something that lasts for a very short time. It is unrelated to the feeling of trepidation.