Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R.$
Assertion $A :$ Lithium halides are somewhat covalent in nature.
Reason $R :$ Lithium possesses high polarization capability.
In the light of the above statements,choose the most appropriate answer from the options given below:

• A
  Both $A$ and $R$ are true but $R$ is $NOT$ the correct explanation of $A$
• B
  $A$ is true but $R$ is false
• C
  $A$ is false but $R$ is true
• D
  Both $A$ and $R$ are true and $R$ is the correct explanation of $A$