Over the past ten years cultivated sunflowers have become a major commercial crop, second only to soybeans as a source of vegetable oil.
                    
                
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                Asecond only to soybeans as a source of vegetable oil.
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                Bsecond in importance to soybeans only as a source of vegetable oil
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                Cbeing second in importance only to soybeans as a source of vegetable oil
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                DWhich, as a source of vegetable oil, is only second to soybeans
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                Eas a source of vegetable oil only second to soybeans
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