What Did We Learn from the Results of the  Harrisburg

What did we learn from the results of the  Harrisburg Pennsylvanian and Literary Digest polls?

A) that these were examples of scientific polling
B) that straw polls and biased samples can result in inaccurate polls
C) that most types of polling are highly accurate
D) that phone surveys are the only accurate polls
E) that newspaper surveys are the only accurate polls