单项选择题marywouldliketodisplayacollapsedsectiononhervideocatalogform,shehascreatedasectionbuywhenshedisplaytheformintheclientthesectionalwaysopensexpanded.which oneofthefollowingshouldmarydotocollapsethesection?()
A. nothing. Sections always open expanded
B. modify the section default properties to collapsed
C. modify the form propenties to display all sections collapsed
D. modify the section opened for reading property to auto-collapse