You are expected to evaluate/examine (AO3) the limits of the theory of comparative advantages (HL)
Although comparative advantage is a theory that has helped many countries develop their trading, there are quite a few caveats to it. Here are some you should be able to discuss:
It can lead to overspecialization of a certain good or service countries, causing more worldwide harm than benefit
It is viewed as a "Rich Man's Theory" by poorer countries as it tends to benefit more developed countries more
Factors such as transportation costs are ignored.