In a hypothetical situation: a bacterium lives on the surface of a leaf, where it obtains nutrition from the leaf's nonliving, waxy covering (cuticle) while inhibiting the growth of plant pathogens. If this bacterium gains access to the inside of a leaf, however, it causes disease, harming the plant. If the plant dies, the bacterium and its offspring will decompose the plant. What is the correct sequence of ecological roles played by the bacterium in the situation described above? 1. Nutrient recycler 2. Mutualist 3. Host 4. Pathogenic parasite A. Sequence: 2, 3, 4 B. Sequence: 4, 2, 1 C. Sequence: 1, 2, 4 D. Sequence: 2, 4, 1