GMAT Sentence Correction (SC) | Re: The bowerbirds of Australia derive their name from the fact

I rejected B because for following reason

b) the elaborate bowers of sticks and twigs that the males build and decorate with flowers and other vegetation in order to attract females

That is right next to noun twigs so it should modify twigs. Although if there was comma in between (shown as below), then I would have picked B without any doubt.

b) the elaborate bowers of sticks and twigs , that the males build and decorate with flowers and other vegetation in order to attract females

Can