<span>There are other avenues to find the cure to diseases that do not involve exploiting fetuses.
</span>
1) Variation: there needs to be a difference in the individuals within a population
2) Inheritance: These variable traits must be able to be passed down genetically
3) Growth rate: There needs to be a growth rate that requires a struggle for resources
4) Survival rate: There needs to be a difference in survival rate for the different variation types... certain variations will live
Answer:
The answer is a Carbohydrate!
Because they are non renewable sources of energy and they took billions of years to form.
The answer to your question is
x-rays
