3) When the block method is used to pass the parameters of system calls to the operating system, A) the detailed contents of all parameters are stored in registers B) parameters are pushed onto a stack by the program C) the number of registers limits the number and length of parameters D) the address of the block where parameters are stored is passed via the register 4) Before running a program on a CPU core, the executable file is brought into memory by A) assembler B) linker C) loader D) compiler