Choices 1, 2, and 3 all emit carbon dioxide, not enough to destroy the planet, but they still can cause it over a large amount of time, due to Carbon Dioxide being a greenhouse gas. Therefore, the answer is 4. Bicycles do NOT emit any carbon dioxide at all.
-Genetically modified crops :weather and disease resistant meaning more crops and more food available ensuring food security for many counties
- Vaccinations : immunisation from diseases that previously proved deadly
- Fertility assistance ,prenatal scanning, home pregnancy tests
-research into Alzheimer’s
- provided cancer and heart disease treatment
- enabled growing of organs so waiting lists for transplants get shorter and more lives are saved
A. Alleles lineup independently of the other alleles