Question

which of the following might a physicist choose to study?
a. the amount of salt in human saliva
b. the effects of water pollution on tadpoles
c. the effects of fast pitches on wooden baseball bats
d. the amount of iron in moon rocks

Explanation:

A physicist studies matter and energy. Analyzing the amount of iron in moon rocks (matter) falls within a physicist's purview. Option A (saliva - biology/medicine), B (water pollution - environmental science), and C (wooden bats - materials science/engineering) are more related to other fields.

Answer:

D. The amount of iron in moon rocks