TarunKumar1234
If x & y are integers and y = \(x^2 + x^3\), is y < 0?
Stat1: x < 0
y = \(x^2 (x+1)\); if -1 < x <0 then, y >0. And, if x <-1 then, y <0.
Not Sufficient.Stat2: y < 1; between
0 and 1, y >0 and for rest of the condition , y<0 .
Not Sufficient.Combining both, x <0 and y <1, still we have -1 < x <0 condition valid, in which y >0 and for others, y<0.
Not Sufficient.So, I think E. 
TarunKumar1234, thank you for the soln. If I may point out, just a small oversight, I think, \(x\) and \( y\) are integers.
Please note : \(x \) and \(y\) are integers:
Lets simplify the stem :
\(y = x^2(1+x)\) is \(y < 0\)
I) \(x <0 \)
if \(x=-1\) then \(y =0\) ans. is NO.
if \(x= -2\) then \(y=-4\) ans is YES
INSUFF.II) \(y <1\)
if \(x=-1\) then \(y =0\) Ans. is NO
if \(x=-2\) then \(y = -4\) Ans. is Yes.
INSUFF.1 + 2
\(x= -1\) then \(y=0\) Ans is NO
\(x=-2\) then \(y=-4\) Ans is yes.
Ans- E
Hope it helps.