Answer:
Matching of Part A with Part B
Rutherford ------------ discovered proton nucleus
Bohr----------------------postulated the quantum atom
Dalton-------------------Father of atomic theory
Chadwick --------------discovery of neutron
J.J. Thomson----------discovered the electrons
hence , the matching will be
 2 -- d            Â
 3 -- e         Â
 4 -- b         Â
 5 -- a         Â
 6 -- c         Â