Five events occurred in a sequence: E1, E2, E3, E4, and E5. E1 happened before E3 but after E2. E4 occurred after E3 but before E5. What is the correct sequence of events?
Answer: A. E2, E1, E3, E4, E5
E2 happens first, followed by E1, then E3, E4, and finally E5.