To determine how the author supports the central argument of Passage 2, we should analyze the provided options in the context of what would typically strengthen an argument about share tables in schools.
A. By giving alternatives to having share tables in schools - This option would not directly support the central argument in favor of share tables.
B. By explaining how share tables help students and schools - This option directly supports the argument by providing reasons or evidence on the positive impact of share tables.
C. By describing students who place food on share tables - While this may provide some anecdotal evidence, it does not directly support the central argument as effectively as an explanation of the benefits.
D. By telling what happens to the unclaimed food on share tables - This may provide context but does not support the argument about why share tables are beneficial.
Based on this analysis, the best answer is:
B. by explaining how share tables help students and schools