A wild-type Aspergillus strain is transformed with a plasmid carrying a hygromycin resistance allele,and cells are plated on hygromycin.One resistant colony showed an aberrant type of aerial hyphae.When crossed to wild type,the progeny were 1/2 normal hyphae,Hyg sensitive,and 1/2 aberrant hyphae,Hyg-resistant.The probable explanation is that:
A)the plasmid was inserted in a gene for normal hyphal development. B)the plasmid interfered with hyphal development. C)a mutation arose in a gene for hyphal development on the plasmid. D)a mutation arose in a gene for hyphal development on a recipient chromosome. E)the recipient was a heterokaryon carrying some mutant nuclei.