The Philadelphia chromosome is found in patients suffering from

Read the following statements and choose the correct set of statements :
$(a)$ In sickle cell anaemia the mutant haemoglobin molecule undergoes polymerisation under high oxygen tension
$(b)$ Thalassemia is a qualitative problem
$(c)$ Turner's syndrome,Klinefelter's syndrome are common examples of chromosomal disorders.
$(d)$ Haemophilia is a sex-linked recessive disease

When one or more genes are missing from the middle part of a chromosome,it is called:

Down's syndrome occurs in the $21^{st}$ pair of chromosomes due to the presence of an additional chromosome.

In which genetic condition,each cell in the affected person has three sex chromosomes $XXY$?

$A$ human female with Turner's syndrome: