Final answer:
The correct option for this sentence is 'will have finished' using the future perfect tense. This tense indicates the completion of an action at some point in the future.
Step-by-step explanation:
In this sentence, the correct option is 'will have finished'. This is because we're using the 'future perfect tense', which indicates that an action will have been completed at some point in the future. For instance, in the context of the sentence 'The children ______ their homework by now', if we choose 'will have finished', the sentence implies that you expect the children to have their homework done already. So the full sentence reads: 'The children will have finished their homework by now.'
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