1968: Write in chronological order"
(i) Man's landing on moon.
(ii) Discovery of radio activity.
(iii) First nuclear explosion.
(iv) Launching of first satellite by India.
(a) (iii), (ii), (iv), (i)
(b) (i), (ii), (iii), (iv)
(c) (iii), (i), (iv), (ii)
(d) (ii), (iii), (i), (iv)