Which of the following is the widest part of the alimentary canal?

The stomach is the widest part of the alimentary canal. It is a muscular sac that combines food, digestive juices, and gastric secretions to form a thick, semi-liquid substance known as chyme. 

The stomach has the ability to expand to accommodate large meals, and its walls are made up of muscle tissue that contracts and relaxes in unison to grind and mix the food. 

The small intestine is much narrower and absorbs nutrients from the chyme, which is the partially digested food material that enters the small intestine from the stomach.

Although the large intestine is wider than the small intestine, it is not wider than the stomach.

The rectum is the last section of the large intestine and is where faeces are stored before being eliminated through the anus.