26.下列程序哪个是画一个三角形？（）
A. turtle.forward(100)
turtle.left(120)
turtle.forward(100)
turtle.right(60)
turtle.backward(100)
B. turtle.forward(100)
turtle.left(60)
turtle.forward(100)
turtle.right(60)
turtle.backward(100)
C. turtle.forward(100)
turtle.left(120)
turtle.forward(100)
turtle.right(60)
turtle.forward(100)
D. turtle.forward(100)
turtle.left(120)
turtle.forward(100)
turtle.right(120)
turtle.forward(100)
