Column-I	Column-II
(A) Jawaharlal Nehru laid the foundation stone of the National Museum in	(D) through volcanic activity are potentially rich in cobalt.
(B) The feeling a person develops by practising devotion is unique	(E) Sobha Singh who built many of Lutyens’ buildings before independence.
(C) Scientists believe that underwater mountains formed	(F) a job we most cherish, and bhakti is an excellent activity.

The correct answer is C-D.

To find the correct combination, we need to match the sentence fragments from Column-I with those in Column-II to form grammatically correct and meaningful sentences:
1. Fragment (A): "Jawaharlal Nehru laid the foundation stone of the National Museum in..." requires a time, place, or year to complete the sentence. Looking at Column-II, none of the options (D, E, F) complete this sentence logically or grammatically.
2. Fragment (B): "The feeling a person develops by practising devotion is unique..." does not link logically with (F) "a job we most cherish, and bhakti is an excellent activity." or (E) "Sobha Singh who built many of Lutyens’ buildings before independence."
3. Fragment (C): "Scientists believe that underwater mountains formed..." connects grammatically and logically with (D) "...through volcanic activity are potentially rich in cobalt."
Combining (C) and (D) gives: "Scientists believe that underwater mountains formed through volcanic activity are potentially rich in cobalt." This is a complete, grammatically correct, and factual sentence.

Therefore, the only correct matching pair is C-D.