a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
I would say that C. Is the most correct answer. Hope this helps! :-)
Answer:
The base, it is called a nitrogen base
Explanation:
Make/produce and secrete hormones
Cardiac Muscle, reason its called Cardiac attack when you have that sort of " Heart Attack "