521: From the third century AD when the Hun invasion ended the Roman Empire, the Indian merchants relied more and more on the
(a) African trade
(b) West-European trade
(c) South-East Asian trade
(d) Middle-Eastern trade
522: Match the following research institutes A, B, C and D with their respective location labelled as 1 to 6 in the given rough outline map
A. Central Drug Research Institute
B. National Atlas and Thematic Mapping Organisation
C. National Institute of Ocean Technology
D. Temperate Forest Research Centre
Select the correct answer using the codes given below :
Codes:
(a) A-4, B-3, C-2, D-6
(b) A-4, B-5, C-1, D-6
(c) A-2, B-3, C-4, D-5
(d) A-1, B-6, C-2, D-3