18. The cyclically adjusted price to earnings ratio developed by Robert Shiller was at 17.5 times earnings just before the Black Monday market crash of 1987. It is currently at 30 times earnings. a) Assuming three-month options are readily available on the S&P 500 index, what are two option strategies an investor could utilize to profit if the S&P 500 index drops from its current level over the next 3 months? Each strategy can only involve a single option. (2 marks) b) Rank the strategies in terms of cost and risk. (3 marks)