Aperson with poor range of motion will experience the most difficulty while

Here are the choices based on what I saw during my research.
lifting a 25-pound bag of dog food.
Pushing a shopping cart full of groceries.
Retrieving a box of cereal from an overhead shelf.
Walking longer than one-mile distances.

If you have problem with range of motion, then you lack flexibility. Therefore you have most difficulty while retrieving a box of cereal from an overhead shelf. 

It settles nerves, reduces the tension.