A:in
B:at
C:on
D:for
农业技术员在大田中发现一株矮状穗大的水稻,将这株水稻所收获的种子再种植下去,发育而成的植株之间总会有所差异,这种差异主要来自
—— How much did you _______ on the shirt?——Five hundred yuan.——Oh, It's ______ expensive. I can't take it.