A prospective buyer who has previously always lived in the city is looking at a rural property with a real estate agent. The buyer admits that she doesn't know anything about rural properties. The buyer likes the back yard because it is very large but remarks that a small patch of the yard seems to grow more, and much healthier, grass than any other part of the yard. The agent should recommend a: a. well and septic inspection

b. pest inspection

c. radon test

d. mold inspection