Which of the following is the BEST approach to prevent …

Which of the following is the BEST approach to prevent Cross-site Scripting (XSS) flaws?

A.
Use digital certificates to authenticate a server prior to sending data.

B.
Verify access right before allowing access to protected information and UI controls.

C.
Verify access right before allowing access to protected information and UI controls.

D.
Validate and escape all information sent to a server.