I can be stored as a long term source of energy. what macronutrient am i?

PLEASE HELP!!

Bmust be the answer, as technically all organs move, so a is incorrect. all organs are made of different types of cells, so that isn’t a problem, so c is also incorrect. human hearts are very similar to many other animals’ hearts, so d is also incorrect, yet the heart is made of muscle, which is hard to grow in the lab so it would be correct to say b

Answerweight and height;