Tony lives in a house built in the 1920s and would like to upgrade it to be more energy efficient. He would like to receive tax credits, and he decides to consult his tax preparer for advice. Which of the following would qualify for the energy efficient home improvement credit? Question 3Select one: a. Qualified fuel cell property in service in rental property b. Qualified fuel cell property to heat both the primary residence and a swimming pool c. Advanced main air circulating fans in the taxpayer's office building. d. Qualified solar water heating system in the primary residence