Answer:
Competition for light and resources with grasses
Step-by-step explanation:
Mosses are small, flat brioftas that have no conductive vases, flowers, fruits and seeds. In a situation where a region has an intense density of trees as shown in the question above, mosses may be left with a limited amount of resources necessary for their survival, which will decrease their population. As a result, the moss will compete with other plant species.
In relation to the question above, the population of mosses would decline due to the competition for resources with grasses, this is because grasses have advantages in the absorption of resources, due to their biology.