Which pair of terms describes an add-on that purports to serve a useful function while transmitting user data and displaying pop-up boxes without the user's knowledge or permission?

Hackers are individuals who exploit computer systems, while viruses are malicious programs that replicate and spread. Although related to cybersecurity threats, neither term specifically refers to add-ons that secretly collect user data or display pop-ups. Instead, they represent broader categories of attacks and malware.

Downtime refers to periods when a system is unavailable, while uptime indicates the time it is operational. These terms are related to system performance and reliability but do not describe any software add-ons or their effects on user data or experience. They are unrelated to the context of unauthorized data transmission.

Ethics pertains to moral principles guiding behavior, and cost refers to the monetary value associated with goods or services. These concepts do not describe technical terms related to software behavior or user data transmission, making them irrelevant to the question about malicious add-ons.