The correct answer is indeed option 4. Here`s why:

In option 4, the Markha Valley (I) is paired with Jammu and Kashmir (C). This is accurate as the Markha Valley is a popular trekking route located in Jammu and Kashmir.

Dzukou Valley (II) is coupled with Nagaland (D). This is correct because the Dzukou Valley is a gorgeous valley known for its natural beauty and is found in Nagaland.

Sangla Valley (III) is linked with Himachal Pradesh (B). This is also correct as the Sangla Valley, famous for its breathtaking scenery, is in Himachal Pradesh.

Finally, Yumthang Valley (IV) is matched with Sikkim (A). This is accurate as the Yumthang Valley, also known as the `Valley of Flowers`, is located in Sikkim.

The other options mismatch the valleys with their respective states, thus they are incorrect.