I had this question as well and if you look closely, the question describes the function in terms of rabbits, when the actual question describes fish. I believe that because the question is asking for fish when only information on rabbits has been given, the only logical answer would be e. none of the above...
If the temperature was 3 degrees Fahrenheit at Midnight, and it dropped 7 degrees during the next hour, then the temperature at 1 A.M. would be -4 degrees Fahrenheit. This is true because 3 - 7 = -4.
So, the answer to this question is that the temperature was -4 degrees Fahrenheit at 1 A.M.