Which is the best description of sexual reproduction in plants

Plants reproduce sexually through their flowers. The flowers have both the male and the female organs. Pollens contain the male gametes and the stimage is a long tube connecting to the female organ of ovary that has the female gametes. The pollen grains need to stick to the stigma for the pollination to begin. This can happen in two ways:

a. Self-pollination: When the pollens of the same plant or flower end up on its stigma. This can happen by the force of wind.

b. Cross-pollination: When the pollens of one plant end up on the stigma of the other plant's flower. This happens when insects while visiting a flower get pollen grains stuck on their body and deposit it at the stigma of the other plant's flower when they sit on it.

The best example would be of the Hibiscus and the Yucca plant flower, each of which gets pollinated by insects.

heat a spark and oxygen

phylogenetic tree is the tree of life or evolution tree. it shows the different branches of evolution. the sequence goes like tissues - coelom - backbone - endoskeleton - segmentation