Which of the following are common symptoms of infection?

Fever, fatigue, swelling, pain, and inflammation are well-documented common symptoms of infection. When the body is infected, it mounts an immune response, which often leads to the release of pyrogens that can cause fever. The body's fight against pathogens can leave individuals feeling fatigued as energy resources are diverted to fighting the infection. Swelling and inflammation occur in response to white blood cells moving to the area of infection, while pain may arise due to the resulting inflammation and the impact on the surrounding tissues.

The other options include symptoms that might relate to different conditions or health issues. Rashes and swelling can occur due to allergic reactions or dermatological conditions rather than specific infections. Weight loss and increased appetite do not align with typical infection responses, where appetite often decreases. Muscle spasms and joint stiffness are more characteristic of conditions like arthritis or muscular disorders rather than straightforward infections.