If a tree falls then sunlight becomes available to the surrounding plants, and plants use sunlight for photosynthesis. Given these facts, what can make photosynthesis more accessible to surrounding plants among the following options:
- Energy.
 - a giant earthquake
 - circulatory systems
 - organic molecules
 - a tree falling
 - a huge fire
 - a great flood
 - Solar energy


 

     a tree falling    