प्राथमिक कक्षाओं में पर्यावरण अध्ययन का निम्नलिखित में से कौन सा सबसे महत्वपूर्ण घटक माना जाता है?

Prolonged occupational exposure to excessive noise from heavy machinery without hearing protection causes noise-induced hearing loss. Excess noise is categorized as a:

Long-term exposure to indoor air pollutants, such as smoke from burning biomass fuels, significantly increases the risk of developing chronic respiratory conditions like: