Choose the incorrect statement with respect to monohybrid cross. 

• A

  ${\mathrm{F}}_1$ hybrids of Mendelian monohybrid cross have both the allelic forms of a gene. 

• B

  The genotypic ratio of ${\mathrm{F}}_2$ generation in codominance pattern of inheritance is 1:2:1

• C

  The phenotypic ratio of ${\mathrm{F}}_2$ generation in incomplete dominance pattern of inheritance is 3:1

• D

  Snapdragon shows incomplete dominance pattern of inheritance with respect to flower color.