Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.
Her living conditions were not good. However, she studied very well.
A. Living in difficult conditions forced she to study very well.
B. She studied very well just because she lived in difficult conditions.
C. Difficult as her living conditions were, she studied very well.
D. Living in difficult conditions, she had no choice but to study well.