Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
ROM, URJ, XUG, AXD, ?
Answer & explanation
Correct answer: option 1

Explanation:
ROM, URJ, XUG, AXD, ?
The logic followed here is :
R → (+3) → U → (+3) → X → (+3) → A → (+3) → D
O → (+3) → R → (+3) → U → (+3) → X → (+3) → A
M → (-3) → J → (-3) → G → (-3) → D → (-3) → A
So, the letter-cluster that replaces the (?) to complete the series is "DAA"