The chemical name of ${\mathrm{Na}}_3{\mathrm{PO}}_4$ is:

The formula of the chemical compound, which is the number of atoms it contains, may be used to answer this question by labelling the compound tri, di, hypo, bis, tris, etc.

We have covered the fundamentals of chemistry in our chemistry lessons, including how chemical compounds are named according to conventions like the IUPAC norm and some of their popular names.
We'll examine how these principles are applied to the name of the chemical mentioned above.
- First, there are three sodium atoms, one phosphorus atom, and four oxygen atoms in the formula provided, which is Na₃PO₄.
- The supplied substance is a member of the group of inorganic substances known as alkali metal phosphates. The phosphate group in this instance is PO₄.

So, based on this knowledge, we may conclude that the compound's final name is phosphate.
- Now, because there are three sodium atoms, it is referred to as tri (meaning three). Trisodium phosphate is the only word that may be used to describe this substance as a whole.
Since the molecule has a short name, it may also be referred to as sodium phosphate. By understanding the phosphate group's chemical formula, we can determine the valency of the sodium atom that makes up this compound.

So, the name of the compound is Sodium Phosphate. 

Hence, option A is correct.