Which organs are part of the gastrointestinal tract?

The gastrointestinal tract consists of the organs directly involved in the digestion and absorption of food. This includes the mouth, esophagus, stomach, small intestine, and large intestine.

The mouth is where digestion begins as food is mechanically broken down and mixed with saliva. The esophagus serves as a conduit for food to move from the mouth to the stomach. The stomach further breaks down food using acids and enzymes, while the intestines (both small and large) are crucial for nutrient absorption and waste excretion.

The other options contain organs that do not belong to the gastrointestinal tract, as they either serve different functions or are part of other body systems. For example, the liver, pancreas, and gallbladder assist in digestion but are not part of the tract itself; they produce bile, enzymes, and other substances that aid digestion. Therefore, the correct choice accurately reflects the organs integral to the process of digestion within the gastrointestinal system.