Answer:
A student studying primary succesion should focus on Granite rock.
Step-by-step explanation:
- Primary succession includes the presence of rock and the other elements that break down rocks to form soil and other stuffs.
- As the student is focusing on the study of the primary succession the main topic would be the granite rock.
- The other options relate to the later stage of succession like the Mesquite grassland comes after the primary succession stage.
- Granite rock is the intrusive igneous rock that looks like a granular structure.