Which of the following are true about sharks?

i. Their body fluids is isosmotic to external environment.

ii. They are osmoconformers.

iii. They control their internal environment independent of external environment.

iv. They are osmoregulators.

Given below are two statements.

Statement I - Defecation is an involuntary process that takes place through anal opening guarded by sphincter muscles.

Statement II - Distension, of rectum stimulates pressure sensitive receptors that initiate a neural reflex for egestion.

In light of above statements, select the correct answer from the option given below.

People who consume high protein diet can develop __________ stones.

An organ with sphincters at its origin is