Read the following.

(i) Phenylketonuria causes mental retardation due to accumulation of _A_.

(ii) __B__ is characteristic of sickle cell anaemia.

(iii) $\mathrm{\beta }$ Thalassemia is due to production of __C__ molecules.

In the above A, B, C represent.

	A	B	C
1.	Phenyl pyruvates	Biconcave disc like RBC	Few alpha chains
2.	Phenyl pyruvic acid	Sickle like RBC	Less $\mathrm{\beta }$ chains
3.	Pyruvic acid	Reduced growth	More beta chain
4.	Pyruvic acid	Sickle like RBC	Incorrectly functioning $\mathrm{\beta }$-chain