Multi-choice problem: Continue writing the next sentence in this paragraph:

How to unblock blocked sites
Find a good web-based proxy server.
Proxy servers act as medium, visiting a blocked site for your computer, then showing it to you. Additionally, your ip address and location are not tracked, so you effectively become anonymous online.

Available choices: a. All that's left is to find a good internet server to perform a internet search on. Find a good internet server to perform an internet search on.. b. A good proxy service will not have too many ads or popups. Advertisements are very common and can be a big downside to using many free proxy servers.. c. However, many proxy servers have anti-virus and privacy protection software you can install yourself if necessary. Proxy servers do not require you to set up your own ip address.. d. A reputable proxy server can potentially send viruses or other legal risks to your encrypted web pages, making it your only one option. Set up a virus free proxy server..
b.