A pure line of plants of genotype a/a; b/b; c/c; d/d; e/e(all recessive to wild type) was crossed to a wild type. One F1individual expressed the recessive alleles dand e.

Thisindividual arose most likely from:

A) a deletion in the quadruple homozygous recessive parent.

B) a deletion in the wild-type parent.

C) a gene mutation in the wild-type parent.

D) position effect variegation in the F1.

E) a reversion in the quadruple homozygous recessive parent.