The answer is C. mycorrhizae.
Hope that helped you.
Answer:
Abiotic factor.
Explanation:
Soil type is an abiotic factor for an earthworm. The soil type helps an earthworm to collect food and increase the population.
Sunlight, soil, water, and rocks are those abiotic factors that contribute to earthworms to obtain their food and to survive under the soil or upper side of the soil.
Like earthworms, many other organisms depend on the abiotic factors for their livelihood.
Answer:
a. He is missing a control group of mice that did not receive the new antibiotic.
Explanation:
In any experiment especially experiments testing effectiveness of a drug, there should be a control group.
The importance of a control group is to minimize the effects of other variables other than the independent variable hence increasing reliability of the results.
in this case, a group of mice that did not receive the new antibiotic would have served as the control group.
