The correct answer is option 2. Here`s why:

A. Drishadvati was the Vedic name of the river now called Chautang, so A-2 is correct.

B. Askini is the Vedic name for the river now known as Chenab, which justifies B-1.

C. Vitasta corresponds to the modern Jhelum, therefore C-4 is rightly matched.

D. Lastly, Purushni is the ancient name of the Ravi, so D-3 is also correctly paired.

Therefore, the matching of the Vedic names of the rivers with their modern names as per option 2 is correct, so the other options are incorrect. Remember, this question is based on historical facts, specifically ancient scripts and their modern geographic equivalents.