Here's a problem to solve: Students finished a laboratory experiment using chemicals. The students made sure they safely disposed of the chemicals because they

Among the 4 following options, which is the correct answer?

- A: poured the chemicals down the sink drain.
 
- B: placed the chemicals carefully in the trash can.
 
- C: placed each chemical back in its original container.
 
- D: followed the directions provided by the teacher for each chemical.
 