Linked lists are collections of data items "lined up in a row"-- insertions and deletions can be made anywhere in: a. linked list.
b. Insertions and deletions are made only at one end of a stack, its top.
c. Insertions and deletions are made only at one end of a queue, its tail.
d. Binary trees facilitate high-speed searching and sorting of data.

Why is it uncommon for users to perform searches directly in database tables? a.)users are discouraged from interacting directly with tables because they might confuse tables with spreadsheets. b.) users are discouraged from interacting directly with tables because this may result in unintended changes to source data. c.)users do not have the technical skills required to perform searches directly in database tables. d.)users do not have the permissions required to perform searches directly in database tables.