Which of the following is genetically dominant in man?

Which of the following pairs is $wrongly$ matched?

Match the following:

Column – $I$	Column – $II$
$(1)$ Failure of cytokinesis	$(p)$ To study inheritance of particular traits
$(2)$ Trisomy of $21$	$(q)$ Polyploidy
$(3)$ Error of metabolism	$(r)$ Down's syndrome
$(4)$ Pedigree analysis	$(s)$ Phenylketonuria

Hybrid vigour is due to

The phenotype of an organism is the result of?

Choose the correct option for the given descriptions:
$(i)$ The heterozygous female transmits the disease to the son.
$(ii)$ Change in the shape of the $RBC$ from biconcave disc to elongated sickle-like structure.
$(iii)$ Mentally retarded.
$(iv)$ Haemoglobin is not formed in the proper amount in the blood.