An element is a pure substance that cannot be separated or divided into simpler substances by any method (physical or chemical). The four common elements in all the living organisms are carbon, oxygen, hydrogen, nitrogen.
Thus, the four elements that make up about 96 % of body matter are carbon, oxygen, hydrogen, nitrogen (c).
Explanation:
It is known that the value of Avogadro's number is 
.
Therefore, calculate moles of gold atoms as follows.
Moles of gold atom = 
= 
= 
mol
= 1.99 mol
Thus, we can conclude that 1.99 mol of gold atoms are equivalent to 
atoms.
A neutral atom contains the same number of electrons as protons and that means that the electric charge of the atom is neutral or otherwise known as zero. However, if a particular atom loses an electron, the atom becomes positively charged because there is more protons than electrons.
THIS IS CALLED A CATION.
hope this helps x
