💡 Detailed Explanation
The correct choice is Option 2: 'Because his head hurt very badly and he couldn't get up.' The male student explains his reason for absence: '朝起きたら頭がすごく痛くて、起き上がれなかったんだ' (When I woke up in the morning, my head hurt badly and I couldn't get up). He explicitly denies having a cold ('風邪じゃないんだ'). Therefore, Option 2 is correct.