Forces and elasticity scenario: two trolleys collide and momentum is compared before and after. Which answer best addresses Stretching and deformation and the objective to explain why measurements should be repeated when investigating extension?

The correct answer is: In the collision scenario, apply extension to explain why measurements should be repeated when investigating extension while keeping elastic versus plastic deformation separate.

The correct option is In the collision scenario, apply extension to explain why measurements should be repeated when investigating extension while keeping elastic versus plastic deformation separate.. It is correct because the scenario says two trolleys collide and momentum is compared before and after, which must be interpreted through Stretching and deformation. This directly supports the learning objective to explain why measurements should be repeated when investigating extension. Use values 5, 5, and 10 only if the question asks for a calculation. The answer earns credit by naming the relevant force or motion quantity, using units when needed, and avoiding the boundary error elastic versus plastic deformation.