Which of the following is an example of ecological succession? A
New trees are now providing constant shade, and plants around them that needed sun to survive are being overgrown by shade-dependent shrubbery.

B
Marigolds and sunflowers are planted every year in a flower bed. Both flourish for a few months and then die off at the end of the season.

C
Every spring buds appear on the trees, then they turn into leaves. In the fall, these leaves change colors and die and eventually fall off the trees.

D
Tomato plants growing in a pot are replanted into the ground next to basil and other herbs. All of the plants flourish.