The terms in the given alpha-numeric series follow a certain pattern. However, some terms are missing. Choose the correct sequence of the missing terms from the options given below:

Z_25YB23XC_W_19_E17

A, 21, D, V

The correct answer is Option (4) → A, 21, D, V

Let us rewrite the series clearly by filling the blanks step-by-step:

Z _ 25 Y B 23 X C _ W _ 19 _ E 17

Step 1: Observe the pattern

Each pair of letters is followed by a number.

The number equals:

(Alphabetical position of first letter) − (Alphabetical position of second letter)

Step 2: Verify the pattern

• Z (26) − A (1) = 25
• Y (25) − B (2) = 23
• X (24) − C (3) = 21
• W (23) − D (4) = 19
• V (22) − E (5) = 17

Step 3: Fill the missing terms

So the completed series is:

Z A 25 Y B 23 X C 21 W D 19 V E 17

Missing terms (in order): A, 21, D, V