The answer is A. Excretion I hope this helps
Answer:
Biodervasity.
Explanation:
The term refers to the variety of life on earth.It demonstrates the extent of variation at different levels of species,genetic and ecosystem in a community of organisms.
It not equal in its distribution on earth;but rather varies with the type of ecosystem available and the distribution of biotic and abiotic factors in the ecosystem. For example;
It is highest in the Tropics,due to the species richness and diversity of the region. However, it varies in other ecosystem based on species diversity peculiar to parts of the region .e.g it is highest in the marine ecosystem along the coast of abundant temperature for primary producers.
If an invasive species is added into a food chain/web, it becomes overpopulated/a pest because it has no natural predators.
It can also disrupt the food chain/web by eating the food supplies of the native organism leading to competitions.
The correct answer is A. Experimental group
Explanation:
In experiments, the experimental group refers to the group of subjects that receives special treatment or in which the scientist or researcher intervenes. This is the opposite of a control group that does not receive treatment and therefore, it is used as a reference to measure the effect of the treatment.
This implies, in the experiment presented Group A is the control group as they do not have special treatment because they sleep normally and Group B is the experimental group as the researcher modifies their sleep time and reduces it two hours which means in this group there is a treatment or intervention.