The given series, IV, FR, CN, ZJ, ? Here, the two different patterns are followed, For the first letter, I − 3 = F − 3 = C − 3 = Z − 3 = W For the second letter, V − 4 = R − 4 = N − 4 = J − 4 = F Therefore, the next term is WF. Hence, the correct answer is WF.