命题 " $\exists x>1, x^2-2 x+3>0$ " 的否定形式为 ( )
$\text{A.}$ $\exists x \leq 1, x^2-2 x+3 \leq 0$
$\text{B.}$ $\exists x>1, x^2-2 x+3 \leq 0$
$\text{C.}$ $\forall x \leq 1, x^2-2 x+3 \leq 0$
$\text{D.}$ $\forall x>1, x^2-2 x+3 \leq 0$
$\text{E.}$
$\text{F.}$