If $\frac{dx}{dt}=5$ and $\frac{dy}{dt}=sin(t^2),$ then $\frac{d^{2}y}{d{x}^2}$ is

$2tcos(t^2)$

$($B$)\frac{2tcos(t^2)}{5}$

$\frac{2tcos(t^2)}{25}$

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