Please submit your concern

Explanation:

If y₂ < 40, then Y’s R-index = 87 − y₂ > 47; i.e. 47 < Y’s R-index ≤ 87

If y₂ > 40, then Y’s R-index = 87 – 40 = 47

∴ 47 ≤ Y’s R-index ≤ 87

Similarly,

23 ≤ K’s R-index ≤ 51

33 ≤ R’s R-index ≤ 55          (∵ r₁, s₁ < 28 and r₁ + s₁ ≤ 22)

53 ≤ S’s R-index ≤ 75          (∵ r₁, s₁ < 28 and r₁ + s₁ ≤ 22)
82 ≤ V’s R-index ≤ 130       (∵ v₃, k₃ < 50, v₃ + k₃ ≤ 48)

∴ Any one of Y, K or R could have the lowest R-index.

Hence, option (a).