Figure 2 shows a programmable combinational logic circuit, consisting of a pair of 4-to-1 multiplexers and a 2-to-1 multiplexer. The circuit has been programmed to perform a specific function by setting the data inputs of the 4-to-1 multiplexers to constant values (1's and O's). The input variables of the function are A, B and C (these are applied to the control inputs of the multiplexers). The output of the function is the variable F. 0 0 1 1 D MUX 1 2 0 3 AB MUX F 1 1 MUX 0 E 0 AB Figure 2 Write out and complete the following truth table, giving the values of the variables D, E and F: . B C D EF 0 0 0 1 0 1 1 1 0 0 1 1 1 1 0 1 0 1 1 1