A fruit fly is heterozygous for sex-linked genes when meted with normal female fruit fly, the males specific chromosome will enter egg cell in the proportion

If the ratio between $X$-chromosomes and complete set of autosome is $0.5$. Then the individual will be

Mongoloid condition is related to or In mongolism a patient shows

A man and a woman, who do not show any apparent signs of a certain inherited disease, have seven children ($2$ daughters and $5$ sons). Three of the sons suffer from the given disease but none of the daughters are affected which of the following mode of inheritance do you suggest for this disease