Select the term from the given options that completes the analogy based on the established pattern:

MO18 : ? :: SU34 : TV38 :: WY50 : XZ54

The correct option is NP22.

To complete the given analogy, we analyze the pattern between the terms in the established pairs: SU34 : TV38 and WY50 : XZ54.

Step 1: Pattern for the letters
Each letter shifts forward by 1 position (+1) in the English alphabetical series:

First letter shift:
$\text{S}+1=\text{T}$
$\text{W}+1=\text{X}$

Second letter shift:
$\text{U}+1=\text{V}$
$\text{Y}+1=\text{Z}$

Applying this +1 letter pattern to MO:
$\text{M}+1=\text{N}$
$\text{O}+1=\text{P}$
Thus, the letters for the missing term are NP.

Step 2: Pattern for the numerical values
In each pair, the number in the second term is obtained by adding 4 to the number in the first term:
$34+4=38$
$50+4=54$

Applying the same addition to the number 18:
$18+4=22$

Combining the resulting letters and number yields NP22.