Their purpose is reproduction.
I believe the answer is C.
For number 8:
all radio waves,
infrared radiation,
visible light,
ultraviolet radiation,
X-rays,
gamma rays.
Ans.
Nitrogen fertilizers are commonly used by farmers to increase crop production. Ammonium is the main component of nitrogen fertilizer, as it is easily assimilated by plants and provides nitrogen to them, while nitrate gets easily lost from the soil. During nitrogen cycle, ammonium is converted into nitrate by nitrification. So, nitrification inhibitors are used with to slow down the conversion of ammonium to nitrate to provide nitrogen for longer time.
Thus, 'to increase crop production, nitrification step of nitrogen cycle is preferred by farmers to block, or slow down.'
A Nutrients move through the ecosystem in biogeochemical cycles. A