Given the question: Write a multi-choice question for the following article, with the given choices and answer: Article: Today, many species of animals and plants are endangered. This means they are in danger of becoming extinct and living on only in the pages of history books. The famous dodo is a classic example of a creature that became extinct. A flightless bird that lived on the island of Mauritius, it was discovered by sailors in 1598 but was hunted to extinction by 1681. Hunting has caused the Bengal tiger and the African elephant to be endangered today but habitat destruction can also lead to extinction. This is equally true for plants. Animals and plants disappear for other reasons too, but the main cause is often a disruption(,) in the natural food chain, whether due to hunting, habitat destruction, or even the introduction of alien species. The natural food chain is the cycle that governs the existence of all life on this planet. It is a carefully balanced cycle and any imbalance that occurs can cause knock-on effects that have serious consequences. At the beginning of the natural food chain are plants which turn sunlight into energy and draw nutrients from the earth. Plants are called producers. After the producers come the consumers. There are three tiers of consumers. First are creatures such as plant-eating animals, fish and insects which feed off the producers. These animals that only eat plants are called herbivores. The second tier of consumers are carnivores - animals that live off other animals. The third tier of consumers eats both other animals and plants. These consumers, including most humans, are called omnivores. After animals and plants die, they become food for other smaller creatures, such as bacteria and some plants, such as fungi. As they feed, these creatures turn the dead bodies back into gases and minerals which are again food for the producers at the beginning of the food chain. And so the cycle continues. All of nature is connected and governed by hundreds of these delicate food chains and if a single plant in the chain cannot survive, then the insects that live off the plant start to die and... Options: A Survival of the fittest. B Endangered animals and plants. C How to protect the natural environment. D The link between food chains and extinction. Answer: D The link between food chains and extinction. Question:
The answer is:
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