Assume That a DGS-Like Phenotype Was Produced in a Specific

Multiple Choice

Assume that a DGS-like phenotype was produced in a specific "gene-knockout" mouse, one lacking expression of HA3, a Hox gene known to be involved in developmental regulation in the mouse.
The phenotype of the HA3 knockout can be ascertained by

A) a bone marrow biopsy.
B) an assay for environmental agents known to cause birth defects.
C) a chest X-ray.
D) the measurement of the proportion of CD4 cells to total lymphocytes.
E) an autopsy examination of the adrenal glands.