Series : NIP, KGO, HEN, ECM, ? The pattern followed in each letter of the terms is : 1st letter : N (-3 letters) = K (-3 letters) = H (-3 letters) = E (-3 letters) = B 2nd letter : I (-2 letters) = G (-2 letters) = E (-2 letters) = C (-2 letters) = A 3rd letter : P (-1 letter) = O (-1 letter) = N (-1 letter) = M (-1 letter) = L Thus, missing term = BAL