Assertion: Only a boy child could be born with a substitution of glutamic acid by valine on 6th codon of β-chain of haemoglobin.
Reason: The gene for the above mutation is found on Y-chromosome.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not correct explanation of A
(c) A is true but R is false
(d) A and R are false