plant activity impacts the carbon cycle by introducing more carbon dioxide into the atmosphere: carbon dioxide accumulates in the atmosphere, changes temperatures and alters the salinity levels of oceans, disturbing the salt and water balance equilibrium that supports proper growth of marine plants and animals.
The answer is definetly A
When an object falls, its gravitational potential energy is changed to kinetic energy. You can use this relationship to calculate the speed of the object's descent. Gravitational potential energy for a mass m at height h near the surface of the Earth is mgh more than the potential energy would be at height 0.