What is a key ethical advantage of induced pluripotent stem cells compared with embryonic stem cells?

• A. They require embryos to extract cells
• B. They avoid some ethical concerns because they don't require embryos
• C. They are more controversial than embryonic stem cells
• D. They have no medical potential

Answer: (B)

Avoiding embryo destruction is the key ethical advantage of induced pluripotent stem cells. These cells are created by reprogramming adult cells—such as skin or blood cells—back into a pluripotent state, rather than harvesting cells from early-stage embryos. Because no embryos are destroyed in their creation, the major ethical concerns tied to embryonic stem cell research are largely removed. This allows pursuing similar medical goals, like disease modeling, drug screening, and potential therapies, with less controversy. The other statements don’t fit because iPS cells don’t require embryos, aren’t generally more controversial, and they do have meaningful medical potential.