Assertion : Phenylketonuria is a recessive hereditary disease caused by body?s failure to oxidise an amino acid phendylanine to tryrosine, because of a defective enzyme. Reason : It results the presence of phenylalanine acid in urine. [AIIMS 2000]

• A. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
• B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion 
• C. If the assertion is true but the reason is false
• D. If both the assertion and reason are false
• E. If the assertion is false but reason is true