The correct match is A→3,B→4,C→2‌ and ‌D→1‌. ‌ In 1932, James Chadwick discovered uncharged particle in an atom called neutron. Rutherford atomic model or nuclear atom model proposed by Ernest Rutherford which describe atom consist of tiny, dense positively charged nucleus around which electrons continuously move in circular path. Moseley studied X-rays spectra of frequency of X-ray radiation and atomic number. J. J. Thomson conducted his first cathode ray tube experiment to prove that rays emitted from electron gun are inseparable from latent charge.