Understanding the Concept:
This is a letter based number series hidden inside a $3 \times 3$ grid. Each letter stands for its rank in the alphabet, and the goal is to spot how the ranks move across the grid so the missing entry can be worked out.
Key Approach:
Instead of reading along the rows, this method reads down the columns, since a consistent grid pattern must hold in both directions at once. Column 1 is C, G, L; Column 2 is G, L, R; Column 3 is K, Q, ?.
Detailed Explanation:
Convert Column 1 to numbers: C$=3$, G$=7$, L$=12$. The gaps are $7-3=4$ and $12-7=5$, so the gap itself grows by $1$ each step.
Convert Column 2 to numbers: G$=7$, L$=12$, R$=18$. The gaps are $12-7=5$ and $18-12=6$, again growing by $1$ each step, and shifted up by exactly $1$ compared to Column 1's gaps ($5,6$ versus $4,5$).
This tells us Column 3 should follow gaps of $6$ then $7$ (one more than Column 2's $5,6$). Column 3 starts at K$=11$: the first gap, from K to Q, is $17-11=6$, which matches the predicted first gap perfectly.
The second gap should then be $7$, so the missing value is $17+7=24$.
Converting $24$ back into a letter gives X, since X is the $24^{th}$ letter of the alphabet.
Final Answer:
Reading by columns instead of rows leads to the same result, confirming the missing term is X, which is option (b).
\[ \boxed{X} \]