A Researcher Is Trying to Construct a Molecular-Based Phylogeny of the Entire

A researcher is trying to construct a molecular-based phylogeny of the entire animal kingdom. Assuming that none of the following genes is absolutely conserved, which of the following would be the best choice on which to base the phylogeny?

A) genes involved in chitin synthesis
B) collagen genes
C) β-catenin genes
D) genes involved in eye-lens synthesis
E) genes that cause radial body symmetry