The correct answer is lose courage.
A. fit tightly
B. lose courage
C. shake uncontrollably
The correct answer is (B) To lose courage (in the face of difficulty or danger); to flinch; to cower; to be cowed; to give way before; or to shrink with fear.
Quail comes from Middle English quailen (to give away).
Examples of use:
- The braggart quailed when required to use the high board for his dive.
- The prisoner quailed when his punishment was announced.