Which of the following questions would be answered using concepts from chemistry?
a. how much energy is required to lift a crate into a truck?
b. how fast will a sled be moving when it reaches the bottom of a hill?
c. what atoms make up water?
d. how much force is required to throw a ball over a fence?

The answer is part c that is What atoms make up water?

This is because all of the option A, B and D require some sort of Physics to explain.

Such as how much energy is required, How fast or slow will something reach or how much force required on some object.

But option C, it just requires chemistry concepts as it is about the study of atoms and the usage of periodic table using covalent bonding.

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.

the closer the planet is to the sun, the larger the gravity