Mendel published his work on inheritance of characters in $1865$ but it remained unrecognised till $1900$ because

$(a)$ He could not provide any physical proof for the existence of factors

$(b)$ His concept of factors as stable, discrete units that controlled the expression of traits did not find acceptance from the contemporaries

$(c)$ Mendel's approach of using mathematics to explain biological phenomena was totally old

$(d)$ Communication was not easy (as it is now)

Albinism is known to be due to an autosomal recessive mutation. The first child of a couple with normal skin pigmentation was an albino. What is the probability that their second child will also be an albino

If an albino man marries with a normal woman and $50$ offsprings are albino and $50$ are normal, the woman is

Mental retardation in man, associated with sex chromosomal abnormality is usually due to

The diagrammatic representation of the chromosomes of an individual is called