Mark the Correct alternative in the following:
If the roots of 
are two consecutive integers, then 
is
given that roots are consecutive, let they be a, a+1
From the formula for quadratic equation,
(x - a)(x - a - 1)
= x2 - (a + 1)x - ax + a(a + 1)
= x2 - (2a + 1)x + a(a + 1)
then
b2 - 4c = (2a + 1)2 - 4a(a + 1)
= 4a2 + 1 + 4a - 4a2 - 4a
= 1.
1