In Drosophila Melanogaster, the Expression of Genes Ultrabithorax and Antennapedia

Multiple Choice

In Drosophila melanogaster, the expression of genes Ultrabithorax and Antennapedia can normally be observed in the third thoracic segment which bears a pair of legs as well as a pair of halteres. Homeotic mutations associated with these two genes can give rise to remarkable disturbances in the organization of the adult fly: two pairs of wings in the case of Ultrabithorax, and legs in the place of antennae in the case of Antennapedia. Would you expect these to be gain-of-function or loss-of-function mutations?

A) Loss-of-function for both genes
B) Loss-of-function for Ultrabithorax and gain-of-function for Antennapedia
C) Gain-of-function for Ultrabithorax and loss-of-function for Antennapedia
D) Gain-of-function for both genes