How Can Igor Have a Higher GPA Than Desdemona in Hard

Multiple Choice

How can Igor have a higher GPA than Desdemona in hard courses, also have a higher GPA in easy courses, and yet have an overall GPA which is lower than hers?

A) Statement I: It's impossible.
B) Statement II: It could happen. Igor could have taken mostly hard courses while Desdemona took mostly easy courses.
C) Statement III: It could happen. Igor could have taken mostly easy courses while Desdemona took mostly hard courses.
D) Statement IV: It would happen if Igor took more credit hours than Desdemona.
E) Statements III and IV are true.