Answer:
c. altering blood volume
Explanation:
The sympathetic nervous system acts to modulate blood pressure during short-term periods by modifying arterial pressure. The catecholamine hormone levels may be associated with an increase in the blood pressure by narrowing the blood vessels. Catecholamines are hormonal neurotransmitters released by the adrenal glands. These hormones derive from the metabolism of tyrosine amino acids and include, among others, adrenaline, noradrenaline and dopamine.
