This is a question with answer options. Goal: How to mix a carton of juice before serving it

Which of the following methods is more reasonable for accomplishing this goal?

Options: A. Take the carton in one or two hands, and keep it closed. Shake it firmly to make the contents mix together.. B. Take the carton in one or two hands, and open it. Shake it firmly to make the contents mix together.....I think the answer is
A.