When her sister types "ice," she is actually pressing the keys in the following way due to the swapped "E" and "I" keys:
- The key for "i" (which is now in the place of "E") will actually produce "e."
- The key for "c" remains "c."
- The key for "e" (which is now in the place of "I") will actually produce "i."
So when she types "ice," what will appear on the screen is "eci."
The correct response is: eci.