题目

You’ve heard of Charles Darwin, right? The famous scientist who put forward a theory of evolution. You might have just also heard of Alfred Russel Wallace, who worked together with Darwin on the revolutionary work On the Origin of Species^ published in 1859. But what about Patrick Matthew? “Patrick who?” you might ask. Well, Darwin and Wallace got the fame but Matthew did the legwork too. This British horticulturalist (园艺种植家）actually thought about evolution first, as Dr. Mike Weale, geneticist at King’s College London, explains. He says: “Matthew published a brief17．单项式-2x2y的次数是（　　）A．1B．2C．3D．4