I believe the answer's A) toes and feet.
Because the material is heavy, both of your hands are probably holding it, so if you drop it, it can't land on your hands, so B wouldn't be correct.
Most people don't carry heavy items and do extreme contortion at the same time, so C and D wouldn't be correct.
Also, answer A's probably why work shoes (for construction workers or manual laborers) are thicker than say, athlete shoes.
