Answer: A
Explanation:
Ecological succession is the process of change in the species structure of an ecological community over time. The time scale can be decades (for example, after a wildfire), or even millions of years after a mass extinction.
The primary source of stem thickening in plants is the vascular cambium. It is a plant tissue located between the phloem and the xylem and in the root of a vascular plant. It is the source of secondary growth or the radial growth of the stem of a plant.
If the element has not become an ion yet, then there is 73 electrons.
Number of protons = number of electrons**
**only when the element has not form an anion or cation.
The child is administered to use Intravenous immunoglobulin and Pneumocystis caranii pneumonia or PCP prophylaxis. These are used to improve humoral immunity in the child until the time when the transplant is performed.
The child is not recommended to use influenza vaccine in immunodeficiency disease reason being the possibility of acquiring influenza which is severe.
Again the child is not recommended to use varicella vaccine because it can lead to a risk of acquiring chicken pox.
For a child with PCP, we use Dapsone.