Symbiotic bacteria present in the colon of the large intestine of humans produce:

The hardest substance of the vertebrate body is

Identify the incorrect statement from the following.

In humans, the length of the alimentary canal is about (in $\text{ feet}$)

The posterior part of the soft palate hangs down into the pharynx as a small,finger-like projection called the .......

Match the names of glands listed under column $-I$ with the location given under column $-II$, choose the answer which gives correct combination of the alphabets of the two columns.

Column $-I$ (Glands)	Column $-II$ (Location)
$(A)$ Crypts of Lieberkuhn	$(p)$ Loop of duodenum
$(B)$ Pancreas	$(q)$ Stomach
$(C)$ Adrenal gland	$(r)$ Intestine
$(D)$ Gastric gland	$(s)$ Kidney