Here's a problem to solve: Students go on a class field trip to collect insects. Which of these is an important safety rule for the students to follow?

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

- A: Pick up insects with bare hands.
 
- B: Stay with a classmate at all times.
 
- C: Reach under large rocks without looking first.
 
- D: Work away from the group.
 