Select the option that is related to the third term in the same way as the second term is related to the first term.
ORDERS : QOFBTP :: FASTEN : ?

Let's analyze the relationship between ORDERS and QOFBTP by checking the alternating positional offsets:
O (15) + 2 = Q (17)

R (18) - 3 = O (15)

D (4) + 2 = F (6)

E (5) - 3 = B (2)

R (18) + 2 = T (20)

S (19) - 3 = P (16)
The alternating pattern is +2,−3,+2,−3,+2,−3.

Now let's apply this exact pattern (+2,−3,+2,−3,+2,−3) to FASTEN:

F (6) + 2 = H (8)

A (1) - 3 = 24 → X

S (19) + 2 = U (21)
Prepp

T (20) - 3 = Q (17)

E (5) + 2 = G (7)

N (14) - 3 = K (11)

Combining these letters yields HXUQGK.