TOEFL Listening: TPO-TOEFL阅读TPO - XJ2C2UB_X6UKO747N$

According to paragraph 4, each of the following provides evidence about Ganymede's interior EXCEPT A. Ganymede's large size B. measurements of Ganymede's gravity field C. the fact that Ganymede has a magnetic field D. the fact that Ganymede continues to be geologically active