The extreme limit of human noise tolerance is:

Correct option is C

The upper threshold of human noise tolerance is approximately 140 decibels (dB). Exposure beyond this level can cause immediate and irreversible hearing damage. Sounds above 85 dB can also be harmful over prolonged periods. Protective measures are crucial in industrial and loud environments.
Explanation of options: (a) ✘ 210 decibels – This is far beyond human tolerance and can cause internal damage. (b) ✘ 70 decibels – Safe level for prolonged exposure, not the extreme limit. (c) ✔ 140 decibels – Approximates the upper limit of noise humans can tolerate. (d) ✘ 35 decibels – Represents a quiet environment, like a library.