During a fever, the body increases in temperature, which will affect internal chemical reactions by
increasing their activation energy, resulting in an increased reaction rate.
decreasing their activation energy, resulting in an increased reaction rate.
decreasing kinetic energy of the reactants, them overcome the activation energy.

increasing their activation energy, resulting in an increased reaction rate.

Explanation:

Heat is the total energy of molecular motion. If temperature rises, the total amount of energy in the system is higher due to this, molecules will move faster. If molecules move faster chemical reactions can happen at a faster rate. The reaction rate or rate of reaction is the speed at which reactants are converted into products the higher the energy in the system the frequently the atoms will collide hence speeding up reactions.

Well, a fever affects a cell's ability to carry out chemical reactions by increasing their activation energy, resulting in an increased reaction rate.

Explanation:

the abdomen (less formally called the belly, stomach, tummy or midriff) constitutes the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. the region occupied by the abdomen is termed the abdominal cavity. the stomach secretes acid and enzymes that digest food. ridges of muscle tissue called rugae line the stomach. the stomach muscles contract periodically, churning food to enhance digestion. the pyloric sphincter is a muscular valve that opens to allow food to pass from the stomach to the small intestine.