If 'GRIP' is coded as 'JSLU' and 'MALE' is coded as 'PDON', how is 'IRON' coded such that the resulting code also forms a meaningful English word?

Explanation

Pattern: Odd-positioned letters +3 in alphabet, even-positioned letters −3. IRON: I(1,odd)→L, R(2,even)→O, O(3,odd)→R, N(4,even)→K → LORK. Not a word. Alternative pattern (same as GRIP→JSLU: G+3=J, R+1=S, I+3=L, P+4=T? No). GRIP→JSLU: G→J(+3), R→S(+1), I→L(+3), P→U(+5)? Differences: +3,+1,+3,+5. MALE→PDON: M→P(+3), A→D(+3), L→O(+3), E→N(+9)? Consistent +3 for first three then different. IRON: I→L(+3), R→U(+3), O→R(+3), N→Q(+3) → LURQ. Answer: (a) LURQ. Order (heaviest→lightest): R > S(85kg) > Q > T > P > U