Phenotype Question..?

The answer is A (incomplete dominance). In a situation involving full dominance, the presence of the dominant allele would mask any effects from the recessive allele, so the phenotype would look just like an individual with two dominant alleles. In a situation involving incomplete dominance, the effects of the recessive allele aren't completely masked, so the heterozygous individual has a different phenotype than the individual with two dominant alleles.