Because it is direct contact of the molecules in the air and the land that are touching.
Answer and Explanation:
In suspension cultures (liquid media), it has been demonstrated that single cells can regenerate to form an entire plant, and undergoes all the natural stages of embryo development.
Totipotent stem cells give rise to all types of cells including the placenta and embryo in animals.Pluripotent cells on the other hand are cells that are capable of self-renewing into the three different germ layers of an embryo forming an adult without giving rise to placenta. As the embryo grows, it develops into multipotent cells.
D. 5
I hope this helps :)
I would say the first option