Answer: Mechanical Isolation
Explanation:
Mechanical isolation is a type of barrier that prevents the species that are closely related from mating with each other.
It is used in case of plants and animals(here beetles) in which the without compatible sex organs individual of different species will not be able to mate and produce offspring.
Thus, the correct answer is option C
They can also use carbohydrates so I don't know
Phytoplankton serves as food for virtually all the organisms living in an aquatic environment. It is a primary food producer and serves as the foundation of aquatic food web. If there is a decline in the amount of phytoplankton, the organisms which feed directly on the plant may reduce significantly as a result of dire competition for food, this in turn will affect the organisms which feed on the dying out organisms and the trend will move in a similar way until it affect all the organisms living in that particular aquatic habitat.
It controls all the involuntary actions like digestion and beating of our heart
