Which of the following is a characteristic of greenhouse gases?

Greenhouse gases play a crucial role in the Earth's atmosphere by absorbing and radiating heat. This characteristic is essential for maintaining the planet's temperature. When solar radiation reaches the Earth, some of it is reflected back into space, while a portion is absorbed by the surface and then re-radiated as infrared energy (heat). Greenhouse gases, such as carbon dioxide, methane, and water vapor, capture this heat and re-emit it, effectively trapping warmth in the atmosphere. This process, known as the greenhouse effect, is vital for sustaining life, as it keeps the Earth's surface significantly warmer than it would be without these gases.

In contrast, options that state greenhouse gases do not absorb heat or are always toxic do not accurately describe their nature. Additionally, noting that they are exclusively man-made overlooks the presence of natural greenhouse gases, which exist due to processes like volcanic activity and biological respiration. Thus, the characteristic of greenhouse gases absorbing and radiating heat accurately encapsulates their fundamental role in climate regulation.