The Answer appears to be C. Both Statements.
Statement 1. by itself ain't sufficient, Since, we don't know if x or z are +ve or -ve, we will not be able to multiply with x or z.
Statement 2: alone ain't sufficient since it says nothing about w or y.
But this statements says that either both x and z are +ve or both are -Ve.
On clubbing the 2 statements we know that, Now that we know both x and z are +ve or both are -Ve. we can multply with x and z on both sides and determine the req inequality.
