TOEIC・英語 大学生・専門学校生・社会人 6ヶ月前

AかCでどちらが正解かが分からないです。教えていただきたいです。

14. primarily from plant oils, perfumes were used in ancient times as incense in religious rites, in medicines, and later for adornment. (A) Made them (B) They made (0) (C) Made pno (D) By making