Select the incorrect statement out of the following

• A

  The number of electrons shared by an atom when a covalent bond is formed, is called its covalency

• B

  The number of electrons gained or lost by an atom during the formation of ionic bond is called its electrovalency. 

• C

  Electrovalency can also be taken as the number of unit charges on the ion.

• D

  A structure has lowest energy, in general, if he atoms have maximum formal charge.