The main difference between the Readers' Guide to Periodical Literature and resources like EBSCOhost and Expanded Academic ASAP is that the Readers' Guide is
A. a basic index, while the other resources are full databases allowing access to actual articles.
B. only accessed in a library, while the other resources can be accessed online from anywhere.
C. more universally accepted in an academic setting than the other indexes.
D. older and more comprehensive than the newer, online indexes.