Which of the following explanation justifies for not placing hydrogen in either the group of alkali metals or halogens?

• A

  The ionisation energy of the hydrogen is too high for group of alkali metals and too low for the halogens containing group

• B

  Hydrogen atom does not contain any neutron

• C

  Hydrogen is much lighter than the alkali metals or halogens

• D

  Hydrogen can form compounds with almost all other elements