Consider the following statements,
I. Among halide ions, iodine is the most powerful reducing agent.
II. HOCl is stronger acid than HOBr.
III. HF is stronger acid than HCl.
IV. Fluorine is the only halogen that does not show variable oxidation states.
The correct set of statements is
A. I, II and III
B. II and IV
C. I, II and IV
D. I, II, III and IV
