Final answer:
City Y, which has cool temperatures and heavy rains, is most likely to experience landslides, particularly if it is situated in a hilly or mountainous area as per the relief map.
Step-by-step explanation:
Based on the provided weather data for the four cities, City Y, which has experienced cool temperatures with heavy rains, is most likely to experience landslides. Landslides are more likely to occur in areas with heavy rainfall combined with elevated terrains or slopes. If the relief map indicates that City Y is located in a hilly or mountainous area, the risk of landslides would be further amplified by these environmental factors.
It is important to consider both the relief map and the recent heavy rains to evaluate landslide risk. While we do not have the relief map data explicitly stated here, it is likely that regions with significant elevation changes are at higher risk especially when paired with excessive precipitation, which weakens soil and can lead to slope failure.