Which one of the following is the correct sequence in the order of decreasing length of the three structural parts given below of small intestine in the human body?

The correct answer is D because it follows the anatomical measurements of the small intestine. The small intestine is divided into three parts: the ileum, the jejunum, and the duodenum. 1. The Ileum is the final and longest section, measuring approximately 3.5 meters. 2. The Jejunum is the middle section, measuring approximately 2.5 meters. 3. The Duodenum is the first and shortest section, measuring only about 25 centimeters. Therefore, the decreasing order of length is Ileum, followed by Jejunum, and finally Duodenum.