Concept:The class of a lever depends on which part is in the middle: effort, load, or fulcrum.
Explanation:A lever with the effort at the centre is a third-class lever.
In a pair of forceps, the fulcrum is at one end, the load is at the other end, and the effort is applied in the middle.
Therefore, forceps are third-class levers.
A bottle opener has the load in the middle, making it a second-class lever.
Scissors and a beam balance both have the fulcrum in the middle, making them first-class levers.
So, the correct example is the pair of forceps.
Answer:D. a pair of forceps.
