Which one of the following frequencies of a wave in the air can be heard as an audible sound by the human ear?
a. 100,000 hz
b. 10 hz
c. 1,000 hz
d. 0.10 hz

The average range of human hearing is considered to be roughly
from  20 Hz  to  20,000 Hz .

A).  No.  Too high.  You hear nothing.

B).  No.  Too low.  You may hear something that sounds like
                               rapidly pumping wind, but not a sound tone.

C).  Yes.  1,000 Hz is roughly the 'C' on the piano that is
                 two octaves above middle-C .

D).  No.  0.10 Hz is only one wave every 10 seconds.
               A wave at this rate feels like a breezy day.