¿Qué bioelemento presenta la hormona tiroxina producida por la tiroides?
a) Si
b) Zn
c) Co
d) Cu
e) l

Ithink the answer is 56.

If a hydrogen atom is neutral, it must also have  one electron. an oxygen atom (o) has an atomic number of eight (8). this means a neutral oxygen atom has eight protons and eight electrons. the element actium (ac) has an atomic number of 89, so it has 89 protons and 89 electrons in a neutral atom

It's potassium i believe