a coelomate animal has a body cavity that is completely lined by what kind of tissue
Coelom The coelom is the main body cavity in most animals[1] and is positioned inside the body to surround and contain the digestive tract and other organs. In developed animals, it is lined with a mesodermal epithelium. In other animals, such as molluscs, it remains undifferentiated.[clarification needed]
Connective tissue The cells of connective tissue include fibroblasts, adipocytes, macrophages, mast cells and leucocytes.