Mark the letter A, B, C, or D on your answer sheet...

Câu hỏi: Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions.

The medical problems of parents and their children tend to be very similar to because of the hereditary nature of many diseases.

A. their

B. tend to

C. similar to

D. because