If a and b are Positive Integers and a<b, b is not equal to zero, which of the following can give NEGATIVE answer?	Pick one.
A) a+b  B) ab  C) a/2+b/2  D) a-b  E) a^2+b^2
(A)a+b   This cannot be answer. Because a and b are positive integers   All the following options (Except D) should not be an answer.   (D) a-b   If a&gt;0,a-b gives a negative answer.   So the option a-b is answer
<result>D</result>
If a and b are Positive Integers and a<b, b is not equal to zero, which of the following can give NEGATIVE answer?