What Data Allowed Kaspari, Chang, and Weaver (2010) to Conclude

What data allowed Kaspari, Chang, and Weaver (2010) to conclude that ant foraging behavior is affected by nutrient limitation?

A) Recruitment to NaCl was highest where environmental NaCl was highest
B) Recruitment to NaCl was highest where environmental NaCl was lowest
C) Recruitment to sucrose was highest where environmental sucrose was lowest
D) Recruitment to sucrose was lowest where environmental sucrose was highest
E) Recruitment to NaCl was highest where environmental sucrose was lowest