Which idea is depicted by a cross in which the F1 generation resembles both the parents?

In the case of co-dominance the F1 generation resembles both parents. (Co-dominance means phenotype of the heterozygote includes the phenotypes of both homozygotes.)Incomplete dominance means phenotype of the heterozygote is intermediate ( falls within the range) between the phenotypes of the two homozygotes.Dominance means phenotype of the heterozygote is the same as the phenotype of one of the homozygotes.