The least possible Venn diagram for the given statements is as follows,
Conclusions: I. Some At is On → True (Some At which are Below are definitely On as shown in the least possible diagram as all below are on) II. No Below is Up → True (All Below is On and no On is Up means all Below can never be Up.) III. All Below is Up is a possibility → False (All Below is On and no On is Up means no below can be Up as shown in the least possible diagram.) Hence, All except III follow is the correct answer.