Which of the following best describes privacy-enhancing tools (PETs)?

• A. They simply encrypt data at rest.
• B. They primarily optimize network throughput.
• C. They provide a combination of measures to protect privacy and reduce surveillance.
• D. They protect against surveillance, masking our identities or making it impossible for watchers to determine the source of our searches and web page requests.

Answer: (D)

PETs are about reducing what others can learn about you by limiting surveillance. They work by masking your identity and making it hard for observers to determine who you are or where your requests are coming from. That focus on protecting privacy and curbing surveillance is the essence of PETs, which is why describing them as tools that protect privacy and reduce surveillance—including masking identities and the sources of your online activity—is the best fit. Encryption at rest stays useful for protecting data on devices but doesn’t address who is requesting data or where requests originate. Optimizing network performance has no inherent privacy purpose. So the description that highlights protecting privacy by preventing observers from identifying or tracking your searches and web requests best captures what PETs are for.