Adelle receives an artificial hip to ease her arthritis. Kwan receives a pacemaker to regulate his heartbeat. Hector receives a replacement heart valve from a cow. Denise receives a kidney donated by her identical twin.
I gave my students this multiple choice question: Which surgery is most like the way a transgenic organism is made?

Only one answer is correct among these 4 choices:
- Adelle receives an artificial hip to ease her arthritis.
- Kwan receives a pacemaker to regulate his heartbeat.
- Hector receives a replacement heart valve from a cow.
- Denise receives a kidney donated by her identical twin.

Could you tell me which one is correct?

Hector receives a replacement heart valve from a cow.