In the equation: HF + H2O H3O+ + F-
(a) H2O is a base and HF is its conjugate acid.
(b) H2O is an acid and HF is the conjugate base.
(c) HF is an acid and F- is its conjugate base.
(d) HF is a base and H3O+ is its conjugate acid.
(e) HF is a base and F- is its conjugate acid.