As an arresting officer, you confiscate a telephone from a person suspected of trafficking in drugs. You are concerned that his partners might hack into the phone and wipe it clean before you can examine it back at the lab. Fortunately, you have a ________ in your equipment case, so you can stop that from happening.
◦ write blocker
◦ faraday bag
◦ signal scrambler
◦ call blocker