Use the Following to Answer Questions
in the Nematode $\rightarrow$

Multiple Choice

Use the following to answer questions
In the nematode worm C. elegans loss-of-function ced-3 mutations lead to more cells than normal due to a defect in apoptosis. Loss-of-function mutations in ced-9 cause embryonic lethality due to ectopic cell deaths. The phenotype of ced-9; ced-3 double mutants is the same as ced-3 single mutants; that is, there are more cells than normal due to a defect in apoptosis. Genes ced-3 and ced-9 are known to act in the same genetic pathway.
-Which of the following pathways is consistent with the genetic data?

A) ced-3 $\rightarrow$ ced-9
B) ced-9 $\rightarrow$ ced -3
C) ced-3 ced-9
D) ced-9 ced-3