Which of these is responsible for ridding the body of waste?
a) nervous system
b) excretory system
c) circulatory system
d) reproductive system

micro/nanoscale topography surface exhibits many prominent properties and is extensively employed in biomedical device, microfluidic device and energy device fabrication. additionally, the clinical applications of biomaterials can be largely expanded with of nanostructured surfaces.

it's c. (to reduce the greenhouse effect/carbon gasses)