单项选择题

The(①) program means a program written in a high-level language.It is generally translated to an(②)program,which is in a form directly understandable by the computer.The translation is usually done by program called (③). 

The() program means a program written in a high-level language.It is generally translated to an()program,which is in a form directly understandable by the computer.The translation is usually done by program called ().

A.compiler
B.assembler
C.compile
D.transfer