Which of the Following Best Explains Why an Interstellar Ramjet

Multiple Choice

Which of the following best explains why an interstellar ramjet could, in theory, achieve continuous acceleration?

A) It has such a large fuel tank that it will essentially never use up all the fuel it carries.
B) It takes advantage of theoretically possible loopholes in Einstein's theory of relativity.
C) It uses fuel that is more efficient than any other known fuel.
D) Its speed always gets faster because time dilation changes the rate at which time flows.
E) It collects its fuel as it goes, rather than having to carry the weight of fuel along with it.