Assertion $(A)$: $AlCl_3$ exists as a dimer through halogen bridged bonds.
Reason $(R)$: $AlCl_3$ gets stability by accepting electrons from the bridged halogen.

• A
  Both $(A)$ and $(R)$ are true and $(R)$ is the correct explanation of $(A)$
• B
  Both $(A)$ and $(R)$ are true but $(R)$ is not the correct explanation of $(A)$
• C
  $(A)$ is true,but $(R)$ is false
• D
  $(A)$ is false,but $(R)$ is true