2. Given the quadratic trinomial in $x$ with integer coefficients $a x^{2}+b x+c$, when $x$ takes the values $1, 3, 6, 8$, a student recorded the values of this quadratic trinomial as $1, 5, 25, 50$. Upon checking, only one of these results is incorrect. The incorrect result is ( ).
(A) When $x=1$, $a x^{2}+b x+c=1$
(B) When $x=3$, $a x^{2}+b x+c=5$
(C) When $x=6$, $a x^{2}+b x+c=25$
(D) When $x=8$, $a x^{2}+b x+c=50$