Question

Ok not sure we're I'am going wrong on this

Have to find which one senses is correct as written and the other sentence is incorrect as written but I'm not sure where I'm going wrong please help

In his senior year he was captain of the football team, the secretary of his class.
The book, that I left at home, is the one I need for class.
The window, at the back of the house, let's in plenty of sunlight.
Primitive agricultural tools, and bits of Clay pottery were found in the desert.

Answer 1

the first one doesn't need the comma replace it with and
the second one take out the first comma
the third take out the commas
the last one take the comma out