Final answer:
Mastitis typically results in a fever over 100.4°F (38°C), and fevers are generally caused by an upward adjustment of the body's temperature set point, often due to an immune response to infection.
Step-by-step explanation:
Mastitis is an inflammation of the breast tissue that can involve an infection. The condition is often associated with fever and other symptoms. According to medical guidelines, mastitis is commonly accompanied by a fever over 100.4°F (38°C). Therefore, the correct answer to the question is b) 100.4°F (38°C).
When considering the cause of a fever, such as one that may be associated with mastitis or other conditions, it is typically due to b. upward adjustment of the body temperature set point, possibly caused by an immune response to a viral or bacterial infection. The body raises its temperature in an attempt to fight off the invading pathogens.