The endocrine system is comprised of a number of glands that release chemical messengers known as ____ into the ____.neurotransmitters; blood…

The endocrine system is comprised of a number of glands that release chemical messengers known as ____ into the ____.​

a. ​neurotransmitters; blood

b. ​hormones; blood

c. ​hormones; cerebrospinal fluid

d. ​neurotransmitters; cerebrospinal fluid