Pain receptors in the gut and urinary tract may be stimulated by

A. False The intestine may be cut painlessly during operations under local anaesthesia.

B. True Stretch is an adequate stimulus for these receptors.

C. True Chemicals released in inflammation lower the pain threshold (hyperalgesia).

D. True As with a peptic ulcer.

E. True This is the cause of the intermittent pain known as colic.