A. Biological
Explanation: calcium is a metal on the periodic table, when used in the human body as a strengthener for your bones and teeth, it is not a household item being used, we do not have calcium in bottles in our homes. It is not to show off, since no one can see your bones, therefore it is not b. Yes calcium is used in science, but a scientist is not injecting calcium in your body to observe or make a scientific discovery, therefor it’s not d.
