Three of the following letter-clusters are alike in some manner and hence form a group. Which letter-cluster does not belong to that group?

VCDR

1   2    3    4   5    6   7     8    9  10  11  12  13

 A   B   C    D   E    F   G    H    I    J    K    L   M

 ↓    ↓    ↓    ↓    ↓     ↓   ↓    ↓     ↓   ↓    ↓    ↓    ↓

 Z   Y    X   W   V    U   T    S    R   Q   P    O   N

26  25  24  23  22  21  20  19  18  17  16  15  14

THE LOGIC FOLLOWED HERE IS;

1) SXHP,

S → OPPOSITE → H

X → (-8) → P

2) UZFR,

U → OPPOSITE → F

Z → (-8) → R

3) XCCU,

X → OPPOSITE → C

C → (-8) → U

4) VCDR,

V → NOT OPPOSITE → D

C → (-11) → R

Thus, VCDR  does not belong to that group.