- If something is formed from something else then that something else becomes that something
- Sedimentary rocks are formed by sediment compacting together
- Hence, sediment becomes sedimentary rock by sediments compacting together

- Sediment becomes sedimentary rock by sediments compacting together
- Sedimentary rock is a kind of rock
- Therefore, sediment becomes a kind of rock by sediments compacting together

Therefore, sediment becomes a kind of rock by sediments compacting together
Question
In order for sediments to become rock, the sediments are generally

Context
- Sedimentary rock is a kind of rock 
- If something is formed from something else then that something else becomes that something 
- Sedimentary rocks are formed by sediment compacting together