Reaction for statement A 2Al+6HCl(dil)→2AlCl3+3H2 Reaction for statement B is, Al+4HNO3(conc.)→Al(NO3)3+NO+2H2O The crystalline boron does not reacts with boiling HCl. The reaction for statement D is, AlCl3+3H2O→Al(OH)3+3HCl The only correct statement is that Al reacts with dil HCl to liberate H2 gas. Therefore, the correct option is (4)