What is the major export of Australia? Why?

Automotive Industry

Explanation:

Cars and other automobiles are an industry worth over 250 billion US dollars worldwide, with production trending towards efficiency and sustainability.

There is an incredible car culture to be found all across the globe, and the $257 billion-dollar automotive industry caters to the needs of this culture in a brilliant fashion. The industry is not only about the selling of cars and other motor vehicles, but also involves the designing, manufacturing, and repair of them as well.

Iron ore

Explanation:

Australia's Other Notable Exports

Iron ore is a significant export product, accounting for 24% of their total annual exports. Key export destinations for Australia are China ($55.1 billion), Japan ($18.9 billion), South Korea ($11.2 billion), the United States ($8.26 billion) and the United Kingdom ($7.41 billion).