Match List - I with List - II :

	List - I (compound)		List - II (effect/affected species)
(a)	Carbon monoxide	(i)	Carcinogenic
(b)	Sulphur dioxide	(ii)	Metabolized by pyrus plants
(c)	Polychlorinated biphenyls	(iii)	haemoglobin
(d)	Oxides of Nitrogen	(iv)	Stiffness of flower buds

Choose the correct answer from the options given below :

What is A in the following reaction?

The correct sequence of correct reagents for the following transformation is :

The equilibrium constant for the reaction

A(s) $$\rightleftharpoons$$ M(s) + $${1 \over 2}$$O₂(g)

is K_p = 4. At equilibrium, the partial pressure of O₂ is _________ atm. (Round off to the nearest integer)