Savena needed room to move during her speech, but when she arrived to make her presentation, she learned that she would have to use a microphone affixed to a lectern. what was savena's mistake?

The correct answer is not conducting a pre-speech situational analysis

This means that Savena's mistake was that she did not do her research to find out how exactly the setting of the room and objects would be during her speech.  She automatically assumed that her microphone would not be affixed to a lectern and that she would be able to move around during her presentation.