Initially I thought it is a clear A. But there is a trap here.
statement 1) says Each member of set P is the product of -1 and a prime number
that means it can be -2, -3,-5, -7,-11....... and so on....
now it is not certain how many of these numbers will be part of set. if -2 part of the set then -2 is the greatest number. but from statement A it is not certain.
statement 2) says at least one number of even. so it can be -2,-4,-6,-8.... and so on. now this statement alone can not solve the problem.
combining both the statement we get,-2 is the only prime number that is even.
So combining statement 1 and 2 we get the solution