Step 1: Define Corn Laws.
The Corn Laws were tariffs and restrictions on imported grain introduced in Britain in the early 19th century to protect domestic producers.
Step 2: Historical detail.
They were passed in 1815, repealed in 1846 after strong protests led by Anti-Corn Law League.
Step 3: Eliminate options.
Only Britain had Corn Laws; others did not.
Step 4: Conclusion.
Correct answer: (A) Britain.