Which of the following statements is correct?

Improvement of the human race through hereditary qualities is called:

Which of the following is a sex-influenced character?

Read the following statements and identify the correct ones.
$(1)$ Linkage and recombination were first understood in $Lathyrus$ $odoratus$.
$(2)$ Mendel's work was rediscovered by Correns,Tschermak,and de Vries,which was published in $1900$.
$(3)$ $T.H.$ Morgan is considered the father of experimental genetics.
$(4)$ $A$ child born to parents with thalassemia major can be affected by thalassemia.
$(5)$ In birds,the female is homogametic and the male is heterogametic.

Select the incorrect statement from the following.

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