Which of these is not a greenhouse gas?

Concept: Ammonia isn't a greenhouse gas. Methane, carbon dioxide and nitrous oxide are all hothouse feasts. They contribute to the hothouse effect. Ammonia has no effect on the greenhouse effect. 

 Among these options, ammonia isn't a greenhouse gas where the rest of them are considered as greenhouse gases.

A hothouse is a house made of glass that can be used to grow shops. The sun’s radiations warm the shops and the air inside the hothouse. 

The heat trapped outside ca n’t escape out and warms the hothouse which is essential for the growth of the shops