When you are three, the phrase, "but, why?" is especially effective with parents. Even more so if you utilise that particular high pitched tone that pre-schoolers master so well.
If maman says: please don't draw all over the walls with that marker pen (and btw where the hell did you find it, I thought it was hidden), then a well timed, "but, why?" will go down beautifully.
Similarly, always answer a mild reproof along the lines of, "will you please leave the bloody cat ALONE", with, "but, why?"
"Please put your shoes on".
"But, why?"
"Do not put the toilet roll in the toilet"
"But, why?"
"Stop trying to pull my eyelashes off!"
"But, why?"
You will know you have won, when your mother utters the immortal (pre-motherhood boasts of 'I'll never say that', ringing in her ears) words; "because I said so."