Circadian rhythms are biological changes that occur on a 24 hour cycle. The correct option among all the options that are given in the question is the last option or the fourth option. This is the type of system that happens in plants, animals, cyanobacteria and fungi. I hope the answer comes to your help.
The answer is C. Hopes this helps you out. :)
An acquired or hereditary disease of heart muscle, this condition makes it hard for the heart to deliver blood to the body, and can lead to heart failure, which is heart attack.
SO B IS THE ANSWER
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