Which letter cluster will replace the question mark (?) in the following series? MEND, MHNG, MKNJ, ?, MQNP
Correct Answer: MNNM
Subject: History
Explanation: The series pattern is: The first and third letters remain constant (M and N). The second letter shifts by +3 (E->H->K->N->Q) and the fourth letter shifts by +3 (D->G->J->M->P). Hence, the answer is MNNM.