\pie{10/A, 20/B, 30/C, 40/D} 

 \pie[polar]{10/A, 20/B, 30/C, 40/D} 

 \pie[square]{40/A, 30/B, 20/C, 10/D} 

 \pie[cloud, text=inside, scale font]{10/A, 20/B, 30/C, 40/D}