co-dominance is the answer because
Inheritance of Dwarfing in Maize. Demonstrating the heights of plants from the two parent variations and their F1 heterozygous hybrid (centre).
Dominance in genetics is a relationship between alleles of one gene, in which the effect on phenotype of one allele masks the contribution of a second allele at the same locus.[1][2] The first allele is dominant and the second allele is recessive. For genes on an autosome (any chromosome other than a sex chromosome), the alleles and their associated traits are autosomal dominant or autosomal recessive. Dominance is a key concept in Mendelian inheritance and classical genetics. Often the dominant allele codes for a functional protein whereas the recessive allele does not.
