Both inventions were done by teenagers at their times.
Both inventions claimed to help the environment: Boyan Slat's machine would clean up trash floating in ocean. Duro-Aina Adebola, Akindele Abiola, Faleke Oluwatoyin, and Bello Eniola proposed power generation from urine that would not create carbon monoxide.
Unfortunately both inventions were also challenged by more established scientists and engineers.
Option three is correct. And if there is more than one option that you need to pick, also chose two.
B. Combining sentences to use complex structure
This refers to how "eloquently" you can speak or write.
