Answer:
The correct answer would be C. both heterozygous.
There are three phenotypes present in the offspring in the ratio 1:2:1 (red:pink: white).
Thus, it is a case of incomplete dominance in which the dominant allele is not able to express itself completely over the recessive allele in the heterozygous condition.
It leads to the formation of intermediate phenotype in the organism.
Similarly, pink flower is the intermediate phenotype of red and white flowers.
Thus, the genotype of the plant carrying the pink flowers must be heterozygous. So, both the parent plants must be heterozygous.
