Results from the Phoenix Lander and Curiosity Rover Suggest That

Multiple Choice

Results from the Phoenix lander and Curiosity rover suggest that the positive result from the Viking Labeled Release experiment was probably due to

A) the destruction of organic molecules by oxygen released when perchlorates in the soil decomposed on heating
B) terrestrial contamination from the robotic arm which took the samples
C) a malfunction in the experiment
D) high levels of radioactivity in the soil