Be careful when answering, or (even more so) setting the question "Who was the last Liberal Prime Minister of Great Britain?"
The last Liberal leader to be Prime Minister was David Lloyd George. But he only ever led a Coalition governmnent. The last leader of a Liberal government was H. H. Asquith.
If you're ever asked this question, the answer that's expected is probably "Lloyd George". But if you're setting the question, you should make it clear what you mean: the last Liberal leader to be Prime Minister, or the last leader of a Liberal government.
© Haydn Thompson 2017