Answer;
A. leaf to mouse
Explanation;
-Considering the fact that the amount of energy at each trophic level reduces as it moves through an ecosystem from the lowest trophic level which happens to be producers (plants). And about 10 percent of this energy at any trophic level is transferred to the next level since the rest is lost largely through metabolic processes as heat.
-It means that the lower the trophic level the higher the energy obtained, for instance from producers to primary consumers, more energy is passed since it is the first passage of energy.
C. Agar provides a solid surface for bacterial growth.
Agar is a substance obtained from red algae which when added to a culture media, provides a solid surface for the growth of bacteria. When the agar is not added then the culture media remains as the broth and when the agar is added then the broth gets solidified.
Agar is added 1.5-2% in the broth to get solidified. The growth of the bacteria depends on the amount of agar added. Agar is used for the growth of bacteria because it has gel like properties which holds the nutrients evenly and the bacteria can use it accordingly.