Match the structural components of nucleus with their appropriate characteristics.

	Column - I		Column – II
a)	Nucleolus	1)	Associated with ER
b)	Outer nuclear membrane	2)	Prevent mixing of nuclear material and cytoplasm
c)	Perinuclear space	3)	form by fusion of outer and inner nuclear membrane
d)	Nuclear pores	4)	rRNA synthesis

	a	b	c	d
1.	iii	ii	iv	i
2.	iv	i	ii	iii
3.	i	iv	iii	ii
4.	ii	iii	i	iv