Step 1: What is asked.
We need the country that announced its withdrawal from the International Solar Alliance in January 2026.
Step 2: About the ISA.
The International Solar Alliance works to promote solar energy, mainly in sunny tropical countries.
Step 3: Why a country leaves.
A country may withdraw when its energy policy or budget priorities change.
Step 4: The country.
In January 2026, Canada announced its withdrawal from the alliance, citing a review of its climate commitments.
Step 5: Remove others.
The USA, Denmark, and Japan are not the country in this case.
Step 6: Conclusion.
So the country is Canada.
Answer: Canada