In click and edit the note to include who's explanation is correct and why you think so. When you are done then go read other replies & students who you agree with, and questions/rebuttals to others.
Omar is correct. This is taken from "Insolation and Seasons - Student Guide" & the New Vision for Public Schools curriculum. Originally derived from NSTA's Uncovering Student Ideas in Science Another 25 Formative Assessment Probes.