Why Lion is king of jungle?

 As Lion is not the tallest animal in the kingdom, Lion is not the smartest animal in the kingdom, Lion is not the Heaviest animal in the kingdom but Lion is assumed to be the king of jungle Why? The answer is clear as Lion is not smartest, heaviest, tallest but is king just due to their uneven strength and power which helps Lion to have no fear of other species or animals and help to kill their enemy.

                                                                   

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