The three correct answers describing the differences between solar wind and a geomagnetic storm are:
1. **Geomagnetic storms are associated with CMEs; solar wind is associated with the constant activity in the sun.**
2. **Solar wind sometimes results in geomagnetic storms; geomagnetic storms do not cause solar wind.**
3. **Geomagnetic storms occur only occasionally; solar wind is constant.**
These statements highlight how geomagnetic storms are transient events often linked to coronal mass ejections (CMEs), while solar wind is a continuous flow of charged particles from the sun.