Which of the Following Does Not Inactivate an X Chromosome

Question

Which of the following does not inactivate an X chromosome?
A) Mammals
B) Drosophila
C) C. elegans
D) Marsupials

Accepted Answer

Drosophila do not have X-chromosome inactivation like other organisms. Instead, they use a mechanism called dosage compensation to ensure that males and females produce equal levels of X-linked gene products.