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What is the correct way to write sentence 20?
A An hour later we had designs and sketches for a robot. Which could out-babysit any
teenager!
B An hour later we had designs and sketches, they were for a robot that could out-babysit
any teenager!
C An hour later we had designs and sketches. For a robot that could out-babysit any
teenager!
D An hour later we had designs and sketches for a robot that could out-babysit any
teenager!