Explanation:

- The Quad Group, or Quadrilateral Security Dialogue, is a strategic partnership.

- It includes four countries known for their commitment to a free and open Indo-Pacific region.

- Option 1: Australia

- Part of the Quad Group.

- Involved in regional security and economic discussions.

- Option 2: Canada

- Not a member of the Quad Group.

- While engaged in similar discussions, it is not one of the core Quad nations.

- Option 3: India

- Part of the Quad Group.

- Plays a significant role in discussions on regional security and cooperation.

- Option 4: Japan

- Part of the Quad Group.

- Engages actively in the dialogue to promote regional peace.

The correct answer is Option 2: Canada.