The correct answer is "the formation of new brain cell connections as the result of reading a book".
Usually, neuroplasticity is apparent in young children when the central nervous system has an abundance of neurons. This is always in the context of forming new brain cell connections or synapses that will lead the person to access the information quicker. This also exemplifies the principle of use and disuse when it comes to knowledge.
The other choices concerns the skeletal system, cardiovascular system, and the endocrine/reproductive system; all of which do not have a relation with neuroplasticity.
