The correct answer is option d, that is, neurotransmitters.
A neurotransmitter refers to a chemical component, which is discharged at the terminal of a nerve fiber by the introduction of a nerve impulse, and by diffusing across the junction or synapse. It helps in the transfer of the impulse to another muscle fiber, nerve fiber, or some other composition. Acetylcholine is a kind of neurotransmitter, that is, used by neurons in the CNS and the PNS in the control of activities ranging from heart rate and muscle contraction to digestion and memory.
The groundwater is being discharged faster than it is being recharged is the data suggested.
Option D
<h3><u>Ex
planation:</u></h3>
Ground water level is the level of underground storage of water above the impermeable rock layer. The underground water is getting filtered through different layers of permeable rocks before it enters the final layer. So it’s fresh and ready to be consumed as it is taken out. Thus for centuries, it’s being used as the source of drinking water.
But with increasing population, the ground water is being consumed at the rate very faster than it can be refilled from different sources like precipitation, rivers and other water bodies. So its level tends to get lower and lower as this continues until the point it gets finished.
Except the c) sweat gland