Answer:
c. Against vertical integration, because IHH lacked the relevant resources.
Step-by-step explanation:
IHH lacks the relevant resources to produce their own helmets otherwise they wouldn´t be contracting with a Chines firm to make them the Helmets, in that case this is the best option against vertical integration, the best claim in favor of vertical integration would be the fact of not having to worry about the quality of the helmets.