All the astronauts who are orbiting the earth in space capsules are weightless.

A. All the astronauts orbiting the earth in space capsules are weightless.

B. All the astronauts orbit the earth in space capsules are weightless.

C. All the astronauts to orbit the earth in space capsules are weightless.

D. All the astronauts are orbiting the earth in space capsules are weightless.

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