Loss or gain of a segment of $DNA$ results in

Find the incorrect statement among the following:

Number of Barr bodies in $XXXXY$ is

Down syndrome is caused by an extra chromosome in the $21$st pair. What percentage of offspring from an affected mother and a normal father will show the effect of this disorder (in $\%$)?

The condition of sex chromosomes in a male child with Down's syndrome will be:

Match Column $I$ with Column $II$ and find the correct answer.

Column $I$	Column $II$
$(A)$ Aneuploidy	$(i)$ Increase in whole set of chromosomes
$(B)$ Monoploidy	$(ii)$ Loss or gain of a chromosome
$(C)$ Polyploidy	$(iii)$ Two sets of chromosomes
$(D)$ Diploidy	$(iv)$ $A$ single set of chromosomes