Whitch statement best describes the role of calcium in the body ?

Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy,calcium helps our blood clot, nerves send messages and muscles contract. 

When a virus infects a host cell, it uses the cell's machinery to make copies of its own genetic material in a process called replication. finally, during the process of self-assembly, that protein shell and the copies of the virus's genetic material are assembled into new viruses.