Given below are assertion and reason. Point out if both are true with reason being correct explanation (A), both are true but reason is not correct explanation (B), assertion is true but reason is wrong ( C) and both are wrong (D).
Assertion. `Hb^(s)Hb^(s)` is homozygous condition of sickle cell anaemia.
Reason. It occurs due to substitution of glutamic acid by valine at sixth position in `beta`-chain of haemoglobin.
A. A
B. B
C. C
D. D