I’m not sure but I think is the answer C
Answer: Nitrogen is so vital because it is a major component of chlorophyll, the compound by which plants use sunlight energy to produce sugars from water and carbon dioxide (i.e., photosynthesis). It is also a major component of amino acids, the building blocks of proteins.
Explanation:
The correct answer is B, I know this because none of the other answers are even reasonable. For example-
A is wrong because the size of elephant tusk has not changed over time, elephant tusk just grow...
C is wrong because it makes no sense to hunt elephants with no tusk :/
D is completely wrong because tusk have nothing to do with reproduction, those are two completely separate bodily functions.........
The answer is chromosomes. The chromosome contains the DNA nuclei. It contains all the genetic material of the parents.It is often duplicated in the cell metaphase of the cell division. Chromosomes differ from one organism to another. They are often visible under the microscope.