Select the triad that follows the same pattern as that followed by the two triads given below. Both triads follow the same pattern.
GI - KM - OQ
TV - XZ - BD

Given: 

GI - KM - OQ
TV - XZ - BD

Logic: 1st letter + 4 = 3rd letter and 3rd letter + 4 = 5th letter

2nd letter + 4 = 4th letter and 4th letter + 4 = 6th letter

For, GI - KM - OQ

G + 4 = K, K + 4 = O

I + 4 = M, M + 4 = Q

For, TV - XZ - BD

G + 4 = K, K + 4 = O

I + 4 = M, M + 4 = Q

Now, we check each options.

Option (a): DE - GH - JK (Not Follow)

D + 4 $$\neq$$​ G, G + 4 $$\neq$$​ J

E + 4 $$\neq$$​ H, H + 4 $$\neq$$​ K

Option (b): DF - HJ - LN (Follow)​

D + 4 = H, H + 4 = L

F + 4 = J, J + 4 = N

Option (c): FH - IK - LN (Not Follow)​

F + 4 $$\neq$$​ I, I + 4 $$\neq$$​ L

H + 4 $$\neq$$​ K, K + 4 $$\neq$$​ N

Option (d): LM - PQ - TV (Not Follow)​

L + 4 = P, P + 4 = T

M + 4 $$\neq$$​ Q, Q + 4 $$\neq$$​ V

Thus, correct option is (b).