The answer is <span>B. immune cells that are destroyed by HIV
CD4+ are immune cells (white blood cells) and are an important part of the immune system. Their name comes from the presence of CD4 glycoprotein on their surface. HIV uses CD4 glycoproteins on the surface of CD4+ cells to entry into the cells. The consequence is a reduced number of those cells. Therefore, CD4+ immune cells are destroyed by HIV.</span>
A the flowering of the four oclock plant at the same time
Explanation: Survivorship curves fit three types. A Type I curve shows a low death rate in early and middle life but the death rate increases steeply in old age. A Type II curve shows a death rate is more constant throughout the lifetime of the species.
Probably Mary's doctor will not doctor a chronic villus sampling because of her first time pregnancy at the aged of 37 and her doctor ordered so many series of routine screening procedure. The doctor will not order a chronic villus sampling on Mary.