For thousands of years, man has created sweet-smelling substances from wood, herbs48/50Mark the letter A, B, C, or D to indicate the underlined part that needs correction in each of the following questions. For thousands of years, man has created sweet-smelling substances from wood, herbs and flowers and using them for perfumes or medicine.mansweet-smellingusing themorGiải thíchĐáp án C Using them => used them