Answer A:
The organism which provides energy directly and/or indirectly to all of the other organisms is the garden plants.
Step-by-step explanation:
Plants are generally found at the lowest part of the pyramid/food chain. They are also called Autorotrophs because they are the primary producers of energy from which the entire pyramid feeds off.
The other animals/organisms on the pyramid are called Heterotrophs because they depend directly or indirectly on the primary energy producers.
Answer B:
The Slug and the Aphid feed are herbivorous. So they are in competition for the garden plants. If one of them, for some reason, decreased in population, the other will have more food to eat.
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