How long will it take to empty the tank if both the inlet pipe A and the outlet pipe B are opened simultaneously? I. A can fill the tank in 16 minutes. II. B can empty the full tank in 8 minutes.

1. A Option A: I alone sufficient while II alone not sufficient to answer
2. B Option B: II alone sufficient while I alone not sufficient to answer
3. C Option C: Either I or II alone sufficient to answer
4. D Option D: Both I and II are not sufficient to answer
5. E Option E: Both I and II are necessary to answer

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