Step 1: Understand the question.
We must find the country hosting the Commonwealth Games in 2026. These Games bring together athletes from Commonwealth nations every four years.
Step 2: Recall the host pattern.
The host country changes each edition. So we just need to remember which country was chosen for 2026.
Step 3: Look at the options.
The choices are UK, Sri Lanka, Australia, and India. We pick the one confirmed to host the 2026 edition.
Step 4: Identify the host.
The 2026 Commonwealth Games are set to be held in Australia, with Australia stepping in as the host nation.
Step 5: Rule out the others.
UK, Sri Lanka, and India are not the host for this 2026 edition, so they are distractors.
Step 6: Match with the options.
The third option, Australia, is correct.
\[ \boxed{\text{Australia}} \]