Match the salts given in Column I with their use given in Column II.   

	Column I		Column II
A.	${\mathrm{Hg}}_2{\mathrm{Cl}}_2$	p.	Salt bridge
B.	Agar-Agar	q.	Calomel electrode
C.	0.1 N KCl	r.	Ice cream
D.	Quinhydron	s.	Redox electrode

• A

  A - p ; B - p,s ; C - q,r ; D - q,s 

• B

  A - q ; B - p,r ; C - p ; D - s

• C

  A - q ; B - p,s ; C - p,r ; D - q,s

• D

  A - q,r ; B - q,s ; C - r,s ; D - p,q,s