(d)
Given function
$f(x) = e^{x^{2}} + e^{- x^{2}}$
$g(x) = xe^{x2} + {e^{- x}}^{2}$ and
$h(x) = x^{2}e^{x^{2}} + e^{- x^{2}}$ Are strictly increasing on [0, 1]. Hence, at $x = 1$, the given function attains absolute maximum all equal to $e + \frac{1}{e}$