[A] : Gall stones are pebbie sized structures that formed in the gall bladder.
[R]: Gall stones develop when excess cho- lesterol in the bile precipitates out of solution, trapping calcium and bile salts.
A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false