Final answer:
The vocabulary word sharing the Old English root "secan" with "seek" is "Seized".
Step-by-step explanation:
The word "seek" comes from Old English secan, meaning "to inquire, pursue." The vocabulary word that shares this same root is b) Seized. When a word is annotated into its prefix and stem, we can see its origins more clearly. For example, "seize" in a broader historical context means to take possession of forcibly, which carries a similar notion of actively pursuing something, much like "seek". The two cs often come from a doubling in spelling during the transition from Old English or Latin roots into modern English or from a conjugation of the verb (such as "seize" becoming "seized").