Potassium Hydroxide (KOH) when added to the solution would give the highest pH
Explanation:
Bases or Alkali are associated with high pH while Acidic substances are represented by lower pH value.
In the given option
HCl- is a strong acid hence would have pH less than 7
H2SO4- also an acid with a pH less than 7
KOH- base with a pH higher than 7
H20-neutral compound with pH as 7
KOH is a very strong base and dissociates in aqueous solution to give it's corresponding metallic ion and hydroxyl ions (OH-) which are characteristic property of any base.
