$ABO$ blood groups in humans are controlled by the gene $I$. It has three alleles: $I^A, I^B$ and $i$. Since there are three different alleles, six different genotypes are possible. How many phenotypes can occur?

The $ABO$ blood group is controlled by:

The plasma membrane of the red blood cells has ...$A$... polymers that protrude from its surface and the kind of sugar is controlled by the gene. The gene $I$ has three alleles ...$B$... The alleles and produce a slightly different form of the sugars,while allele $i$ doesn't produce any ...$C$...
Choose the correct option for $A, B$ and $C$.

Multiple alleles are present:

In which of the following crosses will the offspring show the greatest diversity in phenotypes?

Genes located at the same locus of chromosomes are called