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In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Article: Homework can put you in a badmood , and that might actually be a good thing. Researchers from the University of Plymouth in England doubted whether mood might affect the way kids learn. To find out the answer, they did two experiments with children. The first experiment tested 30 kids. Someshapes were hidden inside a different, larger picture. The kids had to find the small shapes while sitting in a room with either cheerful or sad music playing in the background. To test their mood, the scientists asked the kids to point to one of five faces, from happy to sad. Children who listened to cheerful music tended to point to the smiley faces while the others pointed to the unhappy ones. The researchers found that sad kids took at least a second less to find the small shapes. They also found an average of three or four more shapes. In the second experiment, 61 children watched one of two scenes from a film. One scene was happy, and the other was sad. Just like in the first experiment, kids who saw the sad scene acted better compared to the others. The researchers guessed that feeling down makes people more likely to focus on a problem or difficult situation. Not all scientists agree with them, however. Other studies argued that maybe, that cheerful music in the first experiment distracted kids from finding shapes. While scientists work on finding out the answers, it still might be wise to choose when to do your tasks according to your mood. After eating a delicious ice cream, for example, write an essay.
Answer: whether mood affects their learning ability
Solution: Researchers did experiments on kids in order to find out _ .
Why? It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment.

New input: Article: For most of history scientists and mankind in general considered plants to be passive organisms just with no reason or means of communicating with one another. But new research has revealed that many plants actually 'chat' quite a bit over their own networks, which may also indicate that your auntisn't quite as crazy as you thought. You know, the one that talks to her petunias and expects an answer. In fact, many plants form internal communication networks and are able to exchange information efficiently. These connections enable the plants to share information via internal channels in a manner very similar to computer networks. So what kind of things do plants tell each other? Researcher Josef Stuefer found that one purpose for plants having their own "chat systems" is to warn each other. He and his colleagues were the first to prove that clover plants do indeed warn each other via these network links if enemies are nearby. For example, if one of the plants is attacked by caterpillars , it will warn the other members of the network via an internal signal. After receiving a warning, the other plants will strengthen their protective chemical and mechanical resistance so that they are less attractive to advancing caterpillars. This early warning system allows the plants to stay one step ahead of their enemies. Experimental research has revealed that this communication significantly limits the damage to the plants. It is also known that plants have "family values", with new research revealing they have the ability to recognize close s in order to help each other survive. Research found plants from the same species of beach-dwelling wildflowers, for example, grew aggressively alongside unrelated neighbors but were less competitive when they shared soil with their siblings. Some researchers think that plants must communicate through their roots, identifying themselves using tiny chemical signatures specific to each plant's family. The research shows that our current concept of plants is probably a poor reflection of reality. Scientists are eager to discover in what ways, and to what extent, plants communicate with each other.
Answer: by making themselves taste unpleasant
Solution:
We can infer from the passage that clover plants that receive a warning protect themselves against enemies _ .