AttributeError: 'DataFrame' object 没有属性 'str'。 你的意思是：'std'？

Question

I have a PDF file and I'm trying to get the specific data in it using regex but I'm getting the following error.

this is the content of my pdf file: Question.pdf

import re
import tabula
df = tabula.read_pdf('Question.pdf', pages=1,lattice=True)[1]

df.columns = df.columns.str.replace('\r', ' ')
data = df.dropna()
data.str.extract(r'.*\?\s*(.*)')
data.to_excel('data.xlsx', index=False, header=None)

Traceback (most recent call last):
  File "C:\Users\User1\Desktop\test.py", line 7, in <module>
    data.str.extract(r'.*\?\s*(.*)')
  File "C:\Users\User1\AppData\Local\Programs\Python\Python310\lib\site-packages\pandas\core\generic.py", line 5575, in __getattr__
    return object.__getattribute__(self, name)
AttributeError: 'DataFrame' object has no attribute 'str'. Did you mean: 'std'?