Answer:
The corpus callosum
Explanation:
The corpus callosum is the largest white matter structure in the brain. It is located beneath the cerebral cortex and it connects the left and right cerebral hemispheres thus enabling communication between them. The corpus callosum is a bundle of nerve fibers, (axon projections) which transmits neural signals.
The cleanliness of a ecosystem or how healthy it is. It determines how clean an environment/ecosystem is. You need all types of animals living there, therefore making it more healthy. The more healthy, the more we can say that it is biodiverse.
D. nRNA... hope it helps :)
The third one.……...................