Among the halides

(1)  ${\mathrm{BCl}}_3$                                      (2) ${\mathrm{AlCl}}_3$

(3)  ${\mathrm{GaCl}}_3$                                   (4) ${\mathrm{InCl}}_3$

The order of decreasing Lewis acid character is

• A

  1, 2, 3, 4

• B

  2, 3, 4, 1

• C

  3, 4, 2, 1

• D

  4, 3, 2, 1