Which of the following is a common sign of inflammation?

Rubor, or redness, is indeed a common sign of inflammation. It is a result of increased blood flow to the affected area, which is part of the body's immune response to injury or infection. This process involves the dilation of blood vessels as inflammatory mediators are released, allowing more blood to flow to the site where immune cells can respond to pathogens or damage.

In addition to rubor, other classic signs of inflammation include calor (heat), tumor (swelling), dolor (pain), and loss of function. These signs help in identifying areas of inflammation and understanding the body's response.

Increased appetite, fainting, and paralysis are not typical signs of inflammation. Increased appetite generally occurs in response to certain stimuli or conditions, fainting may indicate a drop in blood pressure or other systemic issues, and paralysis is related to nerve dysfunction rather than an inflammatory response. Thus, rubor stands out as a direct indication of inflammation.