There are three MUXes in the EX stage. Among them, the 2 MUXes located at the top is meant to provide correct ALU source data 1 and 2, respectively. The forwarding paths can be denoted as MEM-to-EX-1 (data feedback from MEM stage to EX stage for ALU source data 1), MEM-to-EX-2, WB-to-EX-1, and WB-to-EX-2. They are controlled by control signals, ForwardA and ForwardB.1. Is ForwardA 1-, 2- or 3-bit control signal?