Dr. Khurana and his colleagues synthesized an RNA molecule with repeating sequence of UGN bases (UG UG UG UG UG UG). It produced a tetrapeptide with alternating sequence of cysteine and valine. It proves that codons for cysteine and valine is
(a) UGU and GUU
(b) UGUandGUG
(c) UUG and GGU
(d) GUGandUGU
(e) GUU and UGU