Which of the following is the correct order of floral organs from the outside to the inside of a complete flower?

A) petals → sepals → stamens → carpels
B) sepals → stamens → petals → carpels
C) spores → gametes → zygote → embryo
D) sepals → petals → stamens → carpels
E) male gametophyte → female gametophyte → sepals → petals