There are three stocks, A, B, and C. You can either invest in these stocks or short sell them. There are three possible states of nature for economic growth in the upcoming year (each equally likely to occur); economic growth may be strong, moderate, or weak: The retums for the upcoming year on stocks A,B, and C for each of these states of nature are given below: If you wanted to take advantaze of a ruk-free arbitrage opportunity, you should take a short position in and a long position in an equally weighted portfolio of a. A,B and C b.C. A and B C.A and B,C d. B, A and C