As we didn‘t have an instruction manual, we had to work in how to set up the stereo by trial and error .                                   

C. Identify the one underlined word or phrase - A, B, C or D - that must be changed for the sentence to be correct.

As we didn‘t have an instruction manual, we had to work in how to set up the stereo by trial and error .

                                              A                                                  B             C                                D