The value of John's baseball card collection decreases exponentially over time, and the value of his silver collection increases exponentially over time. If the value of John's two collections combined t years from now is given by the function V = 500(1.05)^2t + 600(0.95)^t, which statement must be true?

A) John's silver collection is more valuable currently than his baseball collection.

B) The value of John's silver collection changes at a faster rate than the value of John's baseball card collection.

C) John's baseball card collection decreases in value by 10% every six months.

D) The total value of the two collections remains constant over time.