How is Geography divided up due to it's being such a broad topic?

Geography is divided into two main categories known as Physical and Human geography

Explanation:

Geography involves the study of the different features and phenomenon which occurs on the earth and other planets.

It is divided into two broad categories known as :

1. Physical Geography which involves the study of the physical features of the earth environment and different occurrences which happens in them.

2. Human geography is the study of the relationship between human activities and the impact on the earth. It also studied how the earth’s processes have varying impacts on humans.

i'm sure the answer you are looking for would be

a. an ice age

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