Answer
$HB$ has the largest $K_a$.
Work Step by Step
1. $K_a$ is proportional to ionization. The larger the $K_a$, the greater is the ionization.
- Therefore, the acid that produces mores $H^+$ and its conjugate base (greatest ionization) is the one with the largest $K_a$
2. Count the amount of protons in each image.
$HA$: 1 proton
$HB$: 4 protons
$HC$: 2 protons
- Since HB has more protons, it is the one with the largest $K_a$.
