ग्रीनहाउस प्रभाव निम्नलिखित में से किस पर्यावरणीय प्रभाव का मुख्य कारण हो सकता है?

Prolonged exposure to extreme cold temperatures may result in tissue damage known as frostbite, which is categorized as a:

In the context of ecosystem energy dynamics, which of the following expressions correctly defines Net Primary Productivity (NPP)?