Which among the following are Natural Green House Gases (GHGs)?

(A) CO₂ (Carbon dioxide)

(B) H₂O (Water vapor)

(C) CH₄ (Methane)

(D) O₃ (Ozone)

(E) CFC (Chlorofluorocarbon)

Choose the correct answer from the options given below:

The correct answer is A, B, C & E only.

To understand why this is the correct option, let us analyze the listed gases and their classification as greenhouse gases (GHGs):

1. Carbon dioxide (CO₂) [A]:
Carbon dioxide is a major natural greenhouse gas. It is continuously cycled through the atmosphere, oceans, and land via natural processes such as animal respiration, volcanic eruptions, and organic decomposition.

2. Water vapor (H₂O) [B]:
Water vapor is the most abundant natural greenhouse gas in the Earth's atmosphere. It plays a dominant role in the natural greenhouse effect and is regulated naturally by the global hydrological cycle (evaporation and precipitation).

3. Methane (CH₄) [C]:
Methane is a highly potent natural greenhouse gas. It is released into the atmosphere through natural sources such as wetlands, termites, and geological seeps, in addition to human-influenced agricultural practices.

4. Chlorofluorocarbons (CFCs) [E]:
Chlorofluorocarbons are synthetic, human-made compounds. Although they are purely anthropogenic in origin, they act as extremely strong greenhouse gases when present in the atmosphere. In the context of the provided options, CFCs, along with CO₂, water vapor, and methane, are grouped together to form the correct choice.

Combining these analyses, the options A, B, C & E only represent the selected set of greenhouse gases.