执行下列程序段后，x=3处的数据点是_______。import numpy as npimport matplotlib.pyplot as pltx = np.arange(8)y = np.arange(8)dot_color = [2, 1, 0, 0, 1, 2, 2, 0]plt.scatter(x,y, c = dot_color,cmap = 'brg')plt.show()
选项：

A:红色;
B:绿色;
C:蓝色;
D:黑色