In individuals with normal lungs, residual volume is determined by:

A. Outward force generated by inspiratory muscles equal to inward recoil of the chest wall
B. Inward force generated by inspiratory muscles equal to outward recoil of the chest wall
C. Inward force generated by expiratory muscles equal to outward recoil of the chest wall
D. Outward force generated by expiratory muscles greater than inward recoil of the chest wall
E. Inward force generated by inspiratory muscles greater than outward recoil of the chest wall