### Explanation

(i) H + G > I + S

(ii) |G – S| = 1

Meaning G and S will be next to each other in the order. So the option A is ruled out.

G not oldest

S not youngest

(iii) No twins

Going by the options, we will try solve the equation,

Taking as example with youngest aged 1, we can try to solve the equation, and correct the age (started with ages 4, 3, 2, 1) to suit conditions (i) and (ii) which gives 5, 4, 3, 1

S I + 4 Generalizing, w can take their ages in terms of I's age,

G I + 3 In this case, H + G > I + S

H I + 2 Since 2I + 5 > 21 + 4