Consider the Following Code Snippet: Public Abstract Class Machine

Consider the following code snippet: public abstract class Machine
{
Public abstract void setRPMs() ;
) . .
}
You wish to create a concrete subclass named PolisherMachine. Which of the following is the correct way to declare this subclass?

A) public class PolisherMachine implements Machine
{
Public void setRPMs() { . . . }
}
B) public class PolisherMachine extends Machine
{
Void setRPMs() { . . . }
}
C) public class PolisherMachine implements Machine
{
Void setRPMs() { . . . }
}
D) public class PolisherMachine extends Machine
{
Public void setRPMs() { . . . }
}