Alex and Felicia each have cats as pets. Alex buys cat food in cylindrical cans that are 6 cm in diameter and 12 cm high. Felicia buys cat food in cylindrical cans that are 12 cm in diameter and 6 cm high. What is the ratio of the volume of one of Alex's cans to the volume of one of Felicia's cans?<spanclass=′latex−bold′>(A)</span>1:4<spanclass=′latex−bold′>(B)</span>1:2<spanclass=′latex−bold′>(C)</span>1:1<spanclass=′latex−bold′>(D)</span>2:1<spanclass=′latex−bold′>(E)</span>4:1