Refining is the technical method used to carry out electronic censorship by blocking Web sites, blogs, forums, or other Internet content from reaching certain audiences.

A __________ attack is a bot attack on a computer system or network that causes a loss of service to users.

A. spam B. phishing C. DDoS D. sniff

__________ code refers to programs that can be shipped unchanged to a heterogeneous collection of platforms and execute with identical semantics.

Fill in the blank(s) with the appropriate word(s).