swapping in mobile system OS, like android is not feasible because (select all that apply) :

a) repeated write operations on flash memory swwap devices could reduce device reliability, leading to failure or memory corruption

b) swapping processes is not a good idea since mobile OS's don't support paging

c) the amount of flash memory on mobile systems is typically small

d) in single- user systems, like smartphones, there is no need to extend the memory space using virtual memory techniques, like swapping and paging.