Many American teenagers have part-time jobs (27) they want to gain work

Read the following passage and mark the letter A, B, C, or D to choose the word or phrase that best fits each of the numbered blanks from 24 to 28.

American teenagers often start high school with a basic plan of classes they must take to get a high school diploma. (24) _____ subjects like English, maths, science, or social studies are required while others can be selected. Schools also provide extracurricular activities like sports, clubs, and bands. American teenagers (25) ______ plan to attend college study hard to get good grades. They are highly motivated and very confident, and (26) ______ responsibility for their learning.
Many American teenagers have part-time jobs (27) ______ they want to gain work experience and learn how to manage their money. The teenage years form an important period of their development that influences adult life. The main goal of this period for most American teenagers is becoming independent, and they work hard both at school and outside school to (28) ______ this goal.
(Adapted from Global Success)