The correct answer is option 1, Australia. The G7 is a group of countries that consists of the world`s largest advanced economies. It was formed in 1975 as the G6 and later expanded to include Canada, France, Germany, Italy, Japan, the United Kingdom, and the United States, becoming the G7. The purpose of the G7 is to discuss and coordinate economic policies, global issues, and international cooperation.

Now let`s analyze the other options:

- Option 2, Canada, is a member of the G7. Canada is one of the founding members of the G7 and actively participates in its meetings and discussions.

- Option 3, France, is also a member of the G7. France is one of the original members and plays an important role in shaping the agenda and policies of the group.

- Option 4, Japan, is also a member of the G7. Japan is a major economy and has been actively involved in the G7`s initiatives and decisions.

Therefore, the only option that is not a member of the G7 is option 1, Australia. While Australia is an important economic player and participates in other international organizations such as the G20, it is not a member of the G7. Alert