C. Vegetation
because even though cows are important, all life is and not just that species and then cars and factories are unnatural and would not be critical for the carbon cycle in nature.
Physical is something you can have/ hold and mental is something in ur head that you can't see or hold.
Diploid refers to a cell that has two copies of each chromosome. One way that a diploid organism could have an offspring that are 3n (triploid) or 4n is when the chromosomes don't separate during meiosis.
Triploid refers to some cell that have 3 copies of each chromosomes for a total of 69 chromosomes.
