Final answer:
The statement is true. Kidneys adjust the amounts of water and electrolytes leaving the body to maintain homeostasis.
Step-by-step explanation:
The statement that kidneys adjust the amounts of water and electrolytes leaving the body so that these equal the amounts of substances entering the body is true.
Homeostasis requires that water intake and output be balanced. The kidneys play a critical role in maintaining this balance by filtering the blood and adjusting the concentration of urine based on the body's water needs. Additionally, the kidneys secrete hormones such as ADH that help regulate water reabsorption and maintain homeostasis.