Task: Question Understanding
Input (English): Question: Winters are cold in Maine, so homeowners must use large amounts of energy to heat their houses. One way to conserve energy is to ___. (A) add insulation to the roof and walls so less heat escapes (B) open windows to increase the circulation of energy (C) turn thermostats to a higher temperature (D) use cheaper fuel for heating?
Output (English): conserve, energy