The key difference between energy flow and matter cycling is that energy flow shows the energy transmission from one trophic level to next trophic level in food chains while matter cycling shows the flow or cycling of elements through the living and nonliving parts of ecosystems
Answer: B). fertilization, diploid
Explanation: During fertilization, the sperm cell (a gamete) fuses with an ovum or egg (a gamete) to form a zygote. Each of the gametes have haploid number of chromosomes (23 chromosomes) and they fuse to produce a zygote with a diploid number (46 i.e., 23 pairs) of chromosomes.
According to Darwin, evolution occurs because of natural selection.