When were earth’s landmasses first recognizable as the continents we know today? a) 10 million years ago b) 135 million years ago c) 180 million years ago d) 300 million years ago

The correct answer is option b, that is, 135 million years ago.  

An ancient supercontinent known as Gondwana started to split about 180 million years ago. The continent then finally differentiated into the landmasses that one is familiar today with as Africa, Australia, South America, the Indian Subcontinent, Antarctica, and the Arabian Peninsula.  

During 170 to 180 million years ago. Gondwana started to split, and South America and Africa separated apart from the other half of the supercontinent. Then about 140 million years ago, Africa and South America split, forming the South Atlantic Ocean between them.  

At the same time, on the other, that is, the eastern part of the supercontinent, Madagascar dissociated from India and both moved away from Antarctica and Australia. However, about 45 million years ago, Australia and Antarctica got split.  

135 million years ago

Explanation:

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