Final Answer:
The type of software that monitors all incoming and outgoing traffic for a computer and blocks suspicious activity is a firewall. Option C is the answer.
Step-by-step explanation:
A firewall is a security software or hardware that acts as a barrier between a computer or network and potential threats from the internet. It monitors all incoming and outgoing traffic, examining the data packets and determining whether to allow or block them based on predefined security rules. Firewalls are crucial for preventing unauthorized access, protecting against malware, and safeguarding sensitive information. Options A (antispyware), B (ransomware), and D (disk cleaner) are not specifically designed for monitoring network traffic; instead, they serve purposes related to spyware protection, ransomware defense, and disk cleanup, respectively.
Option C is the answer.