The answer would be D
Straight away you can eliminate A and C because not all books contain a scientific skill because some may be fiction. C is also wrong because it saids that the ONLY way children can learn is through books which is incorrect.
B is also wrong because reading can be a scientific skill but not always, therefore it is wrong which leaves you with D, the correct answer since it said that it CAN help children learn.
Hope this helps! :3