Explanation:

The given series of letter clusters is $\text{JAM, KEL, LIK, MOJ, ?}$. We need to find the next cluster. Let's analyze the pattern for each letter position in the clusters: 1. **First letter:** $\text{J} (10) \xrightarrow{+1} \text{K} (11) \xrightarrow{+1} \text{L} (12) \xrightarrow{+1} \text{M} (13)$. The pattern is a consistent increment of $+1$. So, the next first letter will be $\text{M} (13) \xrightarrow{+1} \text{N} (14)$. 2. **Second letter:** $\text{A} (1) \xrightarrow{+4} \text{E} (5) \xrightarrow{+4} \text{I} (9) \xrightarrow{+6} \text{O} (15)$. The pattern for the increment is $4, 4, 6$. Assuming the sequence of increments continues as $4, 4, 6, 6$, the next increment should be $+6$. So, the next second letter will be $\text{O} (15) \xrightarrow{+6} \text{U} (21)$. 3. **Third letter:** $\text{M} (13) \xrightarrow{-1} \text{L} (12) \xrightarrow{-1} \text{K} (11) \xrightarrow{-1} \text{J} (10)$. The pattern is a consistent decrement of $-1$. So, the next third letter will be $\text{J} (10) \xrightarrow{-1} \text{I} (9)$. Combining these patterns, the next letter cluster is $\text{NUI}$. Options A, B, C have incorrect second letters based on the derived pattern.