You are a biomedical researcher who is interested in designing a drug to increase bone density. you have decided you can take one of two approaches: (1) design a drug that stimulates bone to be built faster, or (2) design a drug that prevents bone from breaking down. to begin this process, you need to study the cells that would likely respond to either drug 1 or drug 2. which cells are these?

A drug that stimulates bone to be built faster should work on the cell that creates bone. The cell that responsible for bone creation is fibroblast cells. 
A drug that prevents the bone from breaking down should work on the cell that degrades bone. The cell that degrades bone is called osteoclast. 
Osteoclast and fibroblast will work together to maintain the bone density. The process also called bone remodelling.

Yes they are correct good day