That would be temperature. (:
Hope this helps!
After mining, to reclaim the land, the depression is filled with rocks then the top is filled with loosely graded soil. Introduction of early succession plants is important before big trees can grow. The early succession plants help in the breaking down of the rocks into soil hence making the topsoil deeper to support trees.
The right answer is B.
Cholera vaccination is only recommended for staff who have to intervene with patients in an epidemic situation. In all other cases, effective prevention is provided by good personal hygiene (washing hands) and food.
It is also important to know that this vaccine does not protect permanently: It protects only about 90% within 6 months, then to 50% within 3 years.
The goal of a cladogram is to show relationships and evolutionary descent between species.