The correct option is A Secretion of succus entericus
Crypts of Lieberkuhn are simple tubular glands. They occur throught the small intestine between the villi. The glands and intestinal villi are covered by epithelium, which contains multiple types of cells: enterocytes (absorbing water and electrolytes), goblet cells (secreting mucus), enteroendocrine cells (secreting hormones), tuft cells and, at the base of the gland, Paneth cells (secreting anti-microbial peptides) and stem cells. The secretion of this gland is called intestinal juice or the succus entericus, which is alkaline in nature and having pH 8.3.