Since this drawing is his way of reminding her that she and their garden are "as safe as a missel thrush", it makes her one of the many creatures whose secrets he keeps faithfully. So, having that in mind, I would say the correct answer is A) his trustworthiness.
What passages?
I dont see any but i will answer
Must, could, must, must, have, must, have, been, should, have, must
