Option 1: A name of modern computer

This option is incorrect. `Super 301` is not the name of a modern computer. It refers to something else.

Option 2: A new variety of wheat

This option is incorrect. `Super 301` has nothing to do with agriculture or the development of new wheat varieties.

Option 3: American Trade Law

This is the correct answer. `Super 301` refers to a provision in the United States trade law that allows the U.S. government to take action against foreign countries that engage in unfair trade practices. Under `Super 301`, the U.S. can impose trade sanctions or other measures to protect American businesses from unfair competition.

Option 4: A new vaccine for AIDS

This option is incorrect. `Super 301` is not related to medical advancements or the development of a new AIDS vaccine.

In conclusion, `Super 301` is not a modern computer, a new variety of wheat, or a vaccine for AIDS. It is actually a provision in American trade law that addresses unfair trade practices.