Answer:
rainfall/water
Explanation:
The possession of drip tips by the leaves of plants in the rainforest is a form of adaptation against high rainfall. Without the drip tips on leaves, water will persist on the surface of leaves, and in conjunction with the warm climate, promotes the growth of pathogens such as fungi and bacteria.
Hence, the possession of drip tips on leaves is an indication of the prevalence of water in the rainforest region.