B. Protists more closely resemble members of other eukaryotic kingdoms than they do other protists.
Explanation:
It is difficult for scientists to classify protists into one kingdom because they closely resemble member of other eukaryotic kingdoms than they do other protists.
The protists have a wide variations among themselves that makes them very difficult to classify.
Protists have a wide-range of diversity within them and they flaunt every rule used to classify them.
Protists have also shown characteristics of different kingdoms between them.
