Why do I need to answer a skill testing question if I win a prize and am a Canadian resident?

In Canada, games of pure chance are prohibited as illegal lotteries under the Criminal Code.  By adding in a skill-testing question, this makes a sweepstakes appear as a contest and is therefore considered a game of skill which is legal. Often the skill-testing question will appear at the time of confirmation of the winner as part of the acceptance form to complete.