Why does the U.N. Convention on Contracts for the International Sale of Goods (CISG) apply to both the United States and Germany?

a. The CISG convention is considered customary international law. Therefore the USA and Germany should follow the convention.

b.The place of business of the parties are in different countries.

c.The USA and Germany have both ratified the CISG.

d. Only b and c are correct.

e. Only a and c are correct