Pioneer species can decrease if other species move it out. If the pioneer species in a forest area is a type of bush, that bush might decrease in number as more species come in.
C is the answer..........
Answer:
it would be C, since an abiotic factor is a non-living thing that helps shape the ecosystem.
Explanation:
If you look at A it lists flowers, which are alive. If you look at B it lists bacteria, which is alive. C doesn't list anything thats alive. D lists insects, which are alive.
so if you look up things that can cause an asthma attack it will also show that viruses and bacteria are a cause. with asthma you lungs could already be inflamed as well as your air way wich makes it harder to breath. when you have c-19 it will inflame your lungs even more so it makes it even harder to breath given an asthma attack. more asthma attack now are probably caused by c-19 because it is all over the place and the percent of asthma attack by virus has dramatically increased.