Which of the following is not a difference between schools in puerto rico and schools in los estados unidos? classes are conducted in spanish students wear uniforms there are homeschooling options students study both spanish and english

The question ask to choose among the following choices that is not a difference between schools in Puerto Rico and schools in Los Estados Unidos. Base on the question, the possible answer would be the last choice that states "Students study both spanish and english". I hope this would help 

I’m pretty sure it’s 4, you can check on the calculator