Match the terms in Column-$I$ with their descriptions in Column-$II$ and select the correct option.

Column-$I$	Column-$II$
$(A)$ Dominance	$(1)$ Many genes govern a single character.
$(B)$ Co-dominance	$(2)$ In a heterozygous organism, only one allele expresses itself.
$(C)$ Pleiotropy	$(3)$ In a heterozygous organism, both alleles express themselves fully.
$(D)$ Polygenic inheritance	$(4)$ $A$ single gene influences many characters.

In a complementary gene interaction,calculate the number of phenotypes and genotypes produced in a cross $AaBb \times aaBB$.

Select the group of $CORRECT$ statements.
$I$. If phenotype of offsprings shows only the dominant trait then the parent plants are heterozygous.
$II$. $A$ true breeding line shows stable trait inheritance and expression for several generations.
$III$. In mendelian experiment material,contrasting characters can be easily recognized.
$IV$. When a single gene controls two (or more) different traits,it is called polygene.
$V$. When interactions occurs between the alleles of different genes present on the same or different chromosome it is called intragenic interaction.

Sickle cell anaemia has not been eliminated from the African population because

Choose the correct option regarding genetic disorders and inheritance patterns.

Which of the following statements are incorrect? $(i)$ $ABO$ blood grouping is controlled by gene $I$. (ii) Gene $I$ has four alleles. (iii) $I^A$ and $I^B$ produce the same type of sugar. (iv) $I$ or $i$ produces a different type of sugar. $(v)$ $I^A$ and $I^B$ are incompletely dominant.