Answer: А. large, more heavily populated, economies like China
Step-by-step explanation:
Larger countries like China and the US have a higher population which will mean that domestically, they produce quite a lot and so percentage wise would be able to rely less on foreign trade as they will produce a lot of things for themselves.
Smaller countries like Singapore however, will be unable to produce much of what they need and so will have to engage in foreign trade more than larger countries, percentage wise.
Mathematically speaking. Percentage wise, larger countries will rely less on foreign trade because foreign trade will be less compared to their large economies. The reverse is true for smaller countries.