What is a best practice when passing query parameters from user interface to an apex controller?

What is a best practice when passing query parameters from user interface to an apex controller?
A . Query parameters should be properly sanitized by using JSINHTMLENCODE within the VisualForce Page or Component.
B . String parameters should be trimmed using String.trim().
C . Query parameters should be passed only to Salesforce B2B Commerce classes that you are extending.
D . Query parameters should be stored on a backbone model prior to passing them to the server

Answer: A