Which disease is caused by an $X$-linked recessive gene but is not lethal?

In an organism,pink spot is a sex-linked recessive trait and black hair is dominant to white. If a pink spotted black heterozygous female is mated to a white male which is not spotted,the phenotypic ratio of the offspring would be

Which of the following statements are correct?
$(a)$ The $X$-linked genes are located on the non-homologous region of $X$-chromosomes.
$(b)$ Females with the recessive gene on one $X$-chromosome are carriers.
$(c)$ The carrier female is also severely affected by the disorder.
$(d)$ $Y$-linked genes are located on the homologous region of $Y$-chromosome.
$(e)$ Human males have homomorphic sex chromosomes.
Choose the correct option.

Which of the following phenomena leads to variation in $DNA$?

Read the following statements carefully:
$(1)$ Ploidy is a structural chromosomal abnormality.
$(2)$ Hemophilia is an autosomal recessive disorder in which blood does not clot.
$(3)$ Recombination is one of the factors responsible for evolution.
$(4)$ Genetic mapping allows the determination of the specific location of a gene on a chromosome.
$(5)$ Snapdragon plant is an example of incomplete dominance.
$(6)$ $ABO$ blood grouping shows both dominance and codominance.
Identify the correct and incorrect statements from the given options.

Read the following statements carefully $:-$
$(a)$ Linkage is physical association of genes on a chromosome.
$(b)$ In $Drosophila$, genes of body colour and eye colour are tightly linked on $X$-chromosome.
$(c)$ In honey bee a fertilised egg develops as a male $(drone)$.
$(d)$ In grasshopper males have only one $X$-chromosome besides the autosomes.
$(e)$ $Drosophila$ can complete their life cycle in about two months.
Choose the correct option having all correct options.