当 $0 < x \leqslant \frac{\pi}{4}$ 时,下列不等式成立的是
A
$\int_0^x \mathrm{e}^t \cos t \mathrm{~d} t>x, \int_0^x \mathrm{e}^t(1-\sin t) \mathrm{d} t < x$.
B
$\int_0^x \mathrm{e}^t \cos t \mathrm{~d} t < x, \int_0^x \mathrm{e}^t(1-\sin t) \mathrm{d} t>x$.
C
$\int_0^x \mathrm{e}^t \cos t \mathrm{~d} t>x, \int_0^x \mathrm{e}^t(1-\sin t) \mathrm{d} t>x$.
D
$\int_0^x \mathrm{e}^t \cos t \mathrm{~d} t < x, \int_0^x \mathrm{e}^t(1-\sin t) \mathrm{d} t < x$.
E
F