Better business language to learn: French or German?

I'm a current student at UF seeking to attain an MBA. This Fall, I will depart to Brazil to learn Portuguese and to continue my career abroad; I will be living in Brazil for about 1 year and a half. After that, I shall become a trilingual, since I can speak and write both English and Spanish proficiently already; My first goal is to be able to become fluent and write proficiently the 3 most important languages in the American Continent. But, I'm also thinking about learning a fourth language. So, after I return from Brazil I am planning to finish my degree, while learning another language, abroad in either Germany or France. I am currently undecided on which country I should go to study and which language is more important business wise.