A heap of green leaves is lying in one corner of a park. The green leaves in the heap burn with difficulty because :
(a) they contain a tough material called cellulose
(b) they contain a lot of water
(c) they contain a green pigment chlorophyll
(d) they do not get sufficient oxygen for burning
Question 1
Which of the following serve as green lungs? (a) Green pigment of the plants (b) Forests (c) Kitchen gardens (d) Greenhouse gases