The space shuttle carries astronauts back and forth between Earth and the International Space Station in orbit around our planet. What feature is necessary for the space shuttle to perform its function? The space shuttle must have- A: sufficient mass to provide gravity equal to that of Earth.

B: powerful engines to escape the pull of Earth's gravity

C: enough food for the astronauts to eat for several years.

D: adequate space in which the astronauts can float freely.​