There are many people opposed to stem cell research based on ethical grounds. This is because the stem cells used are most often taken from human embryos.

However, many are still in favor of stem cell research. One of the reasons is
A) that stem cells are widely available.
B) that stem cells can treat diseases with no other cure.
C) that stem cells won't result in negative side effects.
D) that stem cell research is the most cost effective treatment.