Which is a correct scientific notation for the floating$-$point literal: $3478\mathrm{.}904$

Group of answer choices

$3\mathrm{.}4$e$-6$

$3\mathrm{.}478904$e$3$

$0\mathrm{.}3478904$e$-7$

$3\mathrm{.}478904$e$-3$