The answer to this question would be: prostate glands
The term upper end is a bit ambiguous and it should be better to call it the proximal end of the urethra. The upper ends of the urethra, near the bladder, there is an organ called prostate. The prostate is a gland that only found in males as its function was to produce seminal fluid, make it a bit alkali.
Answer: Number 2, aka Solid wastes on land.
Explanation: Bacteria in soil is a natural thing, so it's not polluting the earth. Oxygen in the atmosphere is letting us live, meaning it's not polluting the earth. Fish in rivers is also another natural thing, leaving us with solid wastes on land.
As light intensity increases, the rate of photosynthesis increases. As the intensity decreases, so does the rate of photosynthesis
