Which answer would score higher? Not sure where to start? Explain this Answer A Polydactyly is caused by a dominant allele, so the inherited polydactyly allele is expressed even though the child also has an allele for the usual number of digits. Answer B Polydactyly is caused by an inherited allele, so the polydactyly allele is present even though the child also has an allele for the usual number of digits.