Hint-
Study about the strength of acids and bases.
Concept-
Acids and bases can be differentiated based on their strength as weak
and strong.
Correct option-
Option C is correct.
Explanation- BaCl2 is made up of strong base Ba(OH)2 and strong acid HCl. AlCl3 is made up of weak base Al(OH)3 and strong acid HCl. LiCl is made up of weak base LiOH and strong acid HCl. BeCl2 is made up of weak base Be(OH)2 and strong acid HCl. Ba(OH)2 is strongest base among the given options thus have maximum pH.