Answer:
Although the weight is given and we are asked for the weight, the odd wording of the question implies that we are being asked for the gravitational force on the backpack.
If it is gravitational force that is being requested, then the correct answer is A) 41.16 Newtons.
If it is actual weight being asked for, then none of the answers are correct, as the weight of 4.2 kg is given in the question, and does not match any of the answers.