Answer:
A dominant trait can be described as a trait which arises from a dominant allele. A dominant allele is the one which suppresses the effect of a recessive allele. A recessive trait arises from a recessive allele. For a recessive trait to occur, both the alleles of a gene should be recessive.
For a dominant trait to occur, the gene could have homozygous alleles i.e both the alleles would be the dominant ones or the alleles could be heterozygous i.e one dominant allele and one recessive allele.
Hence, to observe wrinkled seeds both the alleles should be recessive i.e rr.
