Answer:
B. Mining
Step-by-step explanation:
Australia is one of the leading countries in the world when it comes to mining. Taken per capita, it is right there around the top by having the most mines that are active in the world. This is possible because the country has numerous valuable natural resources, so in order to develop and keep strong its economy it exploits these natural resources. Unfortunately, this causes lot of pollution in the areas where there's mining, with the water and air being especially affected. Through the mining, lot of toxic chemicals are released. Some of them end up in the air and worsen its quality significantly, while others end up in the water, usually the groundwater and make it unusable, which is very bad considering that Australia doesn't really have abundance of freshwater at disposal.
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