Answer: D
Explanation: They need not to reply on domestic market for there business goals and opportunities, they need to be proactive in their business, explore new locations,carryout research in other foreign market and develop ideas that will improve their business since the opportunity in the domestic market reduces.
In other words, since the domestic market opportunities are decreasing, that have to spears their tentacles to foreign market for survival .so the best option that fits into the blank is "option D" proactive.