Final answer:
People with disabilities represent about 15% of the world's population. The number of individuals with disabilities is increasing due to factors like aging and chronic health conditions, and many disabilities are not immediately visible. The correct option is c.
Step-by-step explanation:
People with disabilities (PWD) comprise a significant portion of the world's population. The World Health Organization reports that over 1 billion people live with some form of disability, which represents about 15% of the world's population.
This indicates that the correct answer to the student's question is c) 15%. Moreover, due to various factors such as demographic trends and increases in chronic health conditions, the number of people with disabilities is on the rise.
It is also important to note that a large majority of disabilities are not visible. 96% of people with a chronic condition do not have a condition that is visible, and 73% of people with a severe disability do not use a personal assistive device such as a wheelchair or walker. The correct option is c.