Which of the following indicates an infection in nails?

The indication of an infection in nails primarily includes symptoms such as redness and pain. When an infection occurs, the body's immune response causes inflammation, which often manifests as redness around the affected area. Pain is another common symptom, indicating irritation and sensitivity in the nail bed as a reaction to the infection. In a healthy state, nails and surrounding flesh should appear normal without these signs of inflammation.

While color changes might occur with other nail conditions, they don't exclusively point to infection. Increased growth can be a sign of healthy nail growth or other conditions unrelated to infections. A shiny appearance might suggest healthy nails but does not indicate an infection. Thus, the combination of redness and pain is a reliable indicator of an underlying infection affecting the nails.