Based on the information provided, Deer Species A (which feeds on shrubs and young trees) is more likely to be considered invasive. This species has caused a reduction in native plant life due to overgrazing, which in turn has led to soil erosion. Species that negatively impact the local ecosystem and contribute to soil erosion typically fit the definition of invasive species.
Therefore, the correct answer is:
A) Deer Species A (feeds on shrubs and young trees).