Which of the following is a greenhouse gas?

The two gases that contribute most significantly to the greenhouse effect are . . . . . . .

Select the appropriate option regarding the El Niño effect.

The current average temperature of the Earth is $...i...$. If the greenhouse effect were absent,the temperature of the Earth would have been $...ii...$.

Greenhouse effect is primarily due to the presence of:

$CO_2, CH_4, N_2O$ and $CFCs$ are called greenhouse gases because they absorb and emit