In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in each blank.
A (1) ______ thunderstorm rolled across the Delta before dawn, and Sam was (2) _________ by the crack of lightning. He heard raindrops dropping hard against the open windows above the hallway. Then he heard them drip and (3)________ against the wall under the windows not far from his cell. The (4) _______- of his bed was suddenly cool. Maybe today (5) _________ not be so hot.

Select the most appropriate option to fill in blank number 4.

1. A
   openness
2. B
   stiffness
3. C
   softness
4. D
   dampness