Explanation:
शिखर सम्मेलन
summit, summit conference
सम्मेलन
summit, Gathering, palaver
शिखर सम्मेलन
shikhar sammelan
D can be accessed easily. Apex
B. Sequence
There is no specific time listed so its not chronological. No cause and effect relationship, no problem being solved and nothing being compared, therefore, B is the most reasonable answer.