What is the result?

Given the code fragment:
ZonedDateTime depart = ZonedDateTime.of(2015, 1, 15, 3, 0, 0, 0, ZoneID.of(“UTC-
7”));
ZonedDateTime arrive = ZonedDateTime.of(2015, 1, 15, 9, 0, 0, 0, ZoneID.of(“UTC-
5”));
long hrs = ChronoUnit.HOURS.between(depart, arrive); //line n1
System.out.println(“Travel time is” + hrs + “hours”);
What is the result?

A.
Travel time is 4 hours

B.
Travel time is 6 hours

C.
Travel time is 8 hours

D.
An exception is thrown at line n1.