Let’s go through each vegetation zone and its characteristics:
Alpine (A): Alpine vegetation is found at high altitudes where the climate is cold, and the defining characteristic is snow, which matches with I. Snow.
Temperate (B): Temperate vegetation zones are characterized by moderate climates. These regions may experience some frost or snow, but frost is not too common, matching with III. Frost some snow.
Tropical (C): Tropical vegetation zones are found in warmer climates, and they typically do not experience frost. This makes C match with IV. No frost.
Subtropical (D): Subtropical regions are typically warm and experience no frost, matching with II. Frost is rare.
Thus, the correct matching is A-I, B-III, C-IV, D-II, which corresponds to Option (4).