For example, you are pushing a water bottle. The push is a force that is imbalance because there is no other force pushing the water back. So if you push the water bottle, it will move. When it moves, it is also call, "Changing position" because its location changed.
The forces can be either balanced or unbalanced. In balanced type of force the net force acting on the object is zero. The forces acting on both sides cancel out each other.
In unbalanced type of forces, the objects in a particular direction. The net force acting on the object is more than 1. As a result, the object will change its position.
Hence, the correct option is (a) "It will change position".
The atom in a sample of an element must contain nuclei with the same number of protons. If the protons change in number, then the element will modify as well.
