Answer:
The correct answer is - C. It is composed of different kinds of tissues.
Explanation:
An organ is a part of the body that is composed of different types of tissues that form a structure and vascularisation, and capable of the development of a physiological function.
The mesentery is a structure that connects the loops of the small intestine which is made up of the different types of tissue to perform a various functions and is not a part of a particular organ system.