If enough ejecta (mainly ash) is sent into the upper atmosphere, the dust particles will block solar energy causing a decrease in temperature. This has happened in the past. Look for the year without summer caused by a volcanic eruption.
Its is already a balanced equation so the option a.1 would fill in for the blank.
The answer is THE SOMATIC NERVOUS SYSTEM.
The somatic nervous system is part of the peripheral nervous system. It is major function is voluntary movement of the muscles and organs and reflex movement. During the processing of voluntary movement, sensory neurons which transmit information about sight, smell, sound, taste and tactile information carry impulses to the brain and the spinal cord.
