The jazz singer (1927) is historically significant because it featured several scenes with

The Jazz Singer (1927) is historically significant because it featured several scenes with synchronous dialogue.
Synchronous sounds refer to any sounds whose origin can be seen on screen. So, if people are talking, you will see where the words are coming from. This is something that hadn't been done prior to the filming of The Jazz Singer, which was revolutionary.

Id click on the little pic on the camera with the dude running