Given below are two statements: 

Assertion (A): The increasing order or acidity of hydrogen halides is HF<HCI<HBr<HI.
Reason (R): While comparing acids formed by the elements belonging to the same group of the periodic table, H-A bond strength is a more important factor in determining the acidity of an acid than the polar nature of the bond.
 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. (A) is False but (R) is True.
Hint: Down the group acidity of hydrogen halide increases.
Explanation:

In the hydrogen halides, the HI is the strongest acid while HF is the weak acid. It is because while comparing acids formed by the elements belonging to the same group of the periodic table, H-A bond strength is a more important factor in determining the acidity of acid than the polar nature of the bond.

Down the group strength of HI bond decreases because bond dissociation energy decreases. Hence, acidity increases.