Carbon is a key element in many molecules that make up living creatures. The carbon atoms in your body .

A - Were created during the Big Bang
B - Were created when dinosaurs died and were buried by mud
C - Have existed since the beginning of time
D - Were created inside of ancient stars

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .

A. ​it generates energy from carbohydrates.b. it requires activation by oxygen.​c. ​it is used by cells to dispose of excess electrons