Choose the odd one out from the following.

In each option, there are two letters and a number. The pattern followed for all except JR6 is For RV3: R = 18, V 22, so 22-18 = 4. 4 - 1 = 3, and the number 3 matches For EK5: E = 5, K = 11, so 11-5 -6. 6 - 1 = 5, and the number 5 matches. For DG2: D = 4, G = 7, so 7- 4 = 3. 3-1 = 2, and the number 2 matches. But for JR6: J = 10, R = 18, so 18−10=8  However, 8−1=7, but the number given is 6. Hence, JR6 does not follow the same pattern. Thus, the correct answer is (a), JR6.