Consider the following statements:
I. People affected by phenylketonuria are unable to convert tyrosine to phenylalanine.
II. Alzheimer's disease results from accumulation of amyloid protein plaques in the brain.
III. Klinefelter's and Turner's syndromes are the result of non disjunction of the sex chromosomes in either of sexes.
Which of the above statements are true?
1. I and II only
2. I and III only
3. II and III only
4. I, II and III