Consider a 5-stage pipelined processor with Instruction Fetch (IF),…

Final answer: The following statements are correct and explanations are given below.

• "In a pipelined execution, forwarding means the result from a source stage of an earlier instruction is passed on to the destination stage of a later instruction" — This correctly describes forwarding (also called bypassing): values produced by an earlier instruction are routed directly to the stage that needs them in a later instruction (typically to the EX stage), avoiding a wait for register writeback and reducing RAW hazards.

• "In forwarding, data from the output of the MEM stage can be passed on to the input of the EX stage of the next instruction" — This is a common bypass path: data produced or read in MEM can be forwarded to the EX inputs of the following instruction so it can be used immediately without waiting for WB.

• "Forwarding cannot prevent all pipeline stalls" — Forwarding reduces many data hazards but cannot eliminate every stall. For example, a load-use hazard or structural/control hazards may still require inserting one or more stall cycles.

Incorrect statement: "Forwarding does not require any extra hardware to retrieve the data from the pipeline stages" — This is false because forwarding needs additional hardware such as bypass multiplexers, dedicated bypass wires, and a forwarding control unit to detect hazards and select the correct forwarded value.

Summary: The correct statements are the ones describing the forwarding concept, the MEM-to-EX bypass path, and the limitation that forwarding cannot prevent all stalls. The statement denying extra hardware is incorrect.