Answer:
The correct answer is:
d. are unequally distributed around the world.
Step-by-step explanation:
Answer A is not correct because none of the countries in the world can produce enough of every singled product. That is why they are exporting their surpluses and importing what they are lack.
Answer B is also not correct because trade is needed everywhere since the beginning of humanity. Even the first man had to trade.
Answer C is not correct also because countries do not have same level of economical development, which makes differences when it comes to trade.
Answer D is correct because certain countries have more products to trade with and some of them also have monopoly on certain goods, while poor countries are usually depending on them.