Final answer:
The Mirai botnet used IoT devices to launch a disruptive DDoS attack, causing widespread outages, and did not decrypt encrypted traffic.
Step-by-step explanation:
The student asked about the nature of the Mirai botnet incident. The correct answer is that the Mirai botnet was involved in a massive DDoS attack that used a large number of infected Internet of Things (IoT) devices. Contrary to the options provided, the Mirai botnet did not merely have minimal effects; it was quite disruptive, affecting a wide range of services and creating substantial outages. It did not involve decryption of encrypted traffic, but rather exploited the weak security of many IoT devices to create a network of bots (infected devices) which was then used to launch DDoS attacks against specified targets, overwhelming them with traffic