I think its B but I'm not sure .. sorry
Chemical weathering changes the composition of rocks, often transforming them when water interacts with minerals to create various chemical reactions. Chemical weathering is a gradual and ongoing process as the mineralogy of the rock adjusts to the near surface environment.
Answer;
A. Movement in his lower extremities
Explanation;
-The 1st lumbar vertebra or the L1 vertebra is the smallest and most superior of the lumbar vertebrae. As the first vertebra in the lumbar region, the L1 vertebra bears the weight of the upper body and acts as a transition between the thoracic and lumbar vertebrae.
-The lumbar vertebrae contain spinal cord tissue and nerves which control communication between the brain and the legs.
It creates mid-ocean ridges
