Due to an escalating trade war, the portfolio manager of an equity mutual fund anticipates a negative impact on his fund's assets. To protect his investment portfolio, the fund manager would:
A) buy S&P 500 index calls.
B) sell S&P 500 index calls.
C) sell S&P 500 index puts.
D) buy S&P 500 index puts.
Answer: D) buy S&P 500 index puts.