The correct answer is C. humble.
Pompous means having or showing an exaggerated sense of one's own importance or abilities. Humble means having or showing a modest or low estimate of one's own importance.
The other options are not antonyms of pompous.
- Feeble means weak or lacking strength.
- Normal means usual, typical, or expected.
- Mild means not severe or intense.
A pompous person is likely to be seen as arrogant, conceited, or self-important. A humble person is likely to be seen as modest, unassuming, or down-to-earth.