Polypeptide hormones, such as fsh and tsh, and biogenic amine hormones, such as epinephrine and norepinephrine, are all considered hormones.

The hormones are the chemicals, which carry messages from one part of the body to another. They carry all the signals in the chemical form.

The hormones, which are made up of protein molecules are referred as the protein hormones or the peptide hormone. Insulin, glucagon, ACTH, FSH, TSH and PTH are some examples of the peptide hormones.

So, the given blank can be filled with protein.

c should be the answer