In 1910, Mоrgаn did а series оf experiments with the fruit fly Drоsophilа, an organism where females are XX and males are XY. When a mutant male fly with white eyes was crossed with a wild type female with red eyes, none of the F1 progeny had white eyes but 18% of the F2 progeny had white eyes. Unexpectedly, all of these white-eyed F2 flies were males. Based on these results, Morgan concluded that white eyes is caused by a recessive X-linked allele. Suppose Morgan had found that half of the F1 progeny had white eyes but all of these white-eyed F1 flies were females. In this case, a valid hypothesis would be