Using the vertical profile in Figure 1, which layer of the tropical rainforest matches the following description?
'An extreme, exposed environment located between 40 and 60 metres above the forest floor, containing a few giant trees that tower above the surrounding vegetation, subjected to high winds, intense sunlight, and rapid evaporation, requiring adaptations like small, waxy leaves to prevent water loss.'

Forest floor
Understorey
Canopy
Emergent layer