In the following the correct bond order sequence is :

A biodegradable polyamide can be made from :

Match List I with List II :

	List-I Elements		List-II Properties
(a)	Li	(i)	Poor water solubility of $${I^ - }$$ salt
(b)	Na	(ii)	Most abundant element in cell fluid
(c)	K	(iii)	Bicarbonate salt used in fire extinguisher
(d)	Cs	(iv)	Carbonate salt decomposes easily on heating

Choose the correct answer from the options given below :

Which one of the following metal complexes is most stable?