In codominance,the phenotypic ratio is......

If two persons with $AB$ blood group marry and have a sufficiently large number of children,these children could be classified as $A$ blood group : $AB$ blood group : $B$ blood group in $1 : 2 : 1$ ratio. Modern techniques of protein electrophoresis reveal the presence of both $A$ and $B$ type proteins in $AB$ blood group individuals. This is an example of:

. . . . . . is an intragenic interaction.

$A$ gene showing codominance has

If two individuals with $AB$ blood group marry and have a large number of children,the children show $A$,$AB$,and $B$ blood groups in a ratio of $1:2:1$. Since proteins of both $A$ and $B$ types are present in individuals with $AB$ blood group,this is an example of:

All of these obey Mendel's laws except: