Answer: The correct option is (D). 24.
Step-by-step explanation: Given that there are 384 nails in a 16-ounce jar.
We are to find the number of nails per ounce in the jar.
We will be using the unitary method to solve the given problem.
Number of nails in 16 ounce of the jar = 384
Therefore, the number of nails in 1 ounce of the jar will be

Thus, there are 24 nails per ounce of the jar.
Option (D) is the correct option.