Which of the following statements regarding an RDBMS and a spreadsheet application are true? $($Select all that apply.$)$

a$.$

An RDBMS requires an additional statement to save the updates, while a spreadsheet saves changes instantly.

b$.$

A spreadsheet organizes data into rows and columns, whereas an RDBMS does not.

c$.$

An RDBMS supports indexes to quickly find requested data items, while a spreadsheet does not.

d$.$

Both an RDBMS and spreadsheets support referential integrity.