Simulate a weather system through experiments (see figure): insert a partition in the middle of the plastic box to make the same volume of red warm water (representing warm air) and

According to the meaning of the question, cold and warm water is equivalent to cold and warm air mass, with high cold water density and low warm water density at the bottom and above. After the partition is pulled out, an inclined interface will be formed between them. This experiment can roughly simulate the formation process of the front, but it can't show the vertical motion characteristics of the airflow, nor can it show the dominant position of cold and warm water, but only the relative motion characteristics of the two.

So choose: a.