使用tkinter模块，下列Python代码能创建一个输入框的是？（ ）
from tkinter import *
root = Tk()
root.title("test")
e1 = Entry(root)
e1.pack()
root.mainloop()
from tkinter import *
root = Tk()
root.title("test")
e1 = Button(root)
e1.pack()
root.mainloop()
from tkinter import *
root = Tk()
root.title("test")
e1 = Label(root,text='123')
e1.pack()
root.mainloop()
from tkinter import *
root = Tk()
root.title("test")
e1 = Checkbutton(root,text='123')
e1.pack()
mainloop()