This question is based on the Literary Appreciation 'And so Tom awake and we rose in the dark And got with our bags and our brushes to work Though the morni...

Answer Details

Tom is happy and warm because he is doing his duty, which is working with his bags and brushes despite the cold morning. The speaker suggests that if everyone does their duty, they need not fear harm, implying that Tom's warmth is not just physical but also a result of fulfilling his responsibilities. Therefore, the correct answer is that Tom is warm because he is doing his duty.