Which of the Following Statements About Columnar Databases A), B)

Which of the following statements about columnar databases a) , b) or c) is false?

A) A columnar database is similar to a relational database, but it stores unstructured data in columns rather than rows.
B) Because all of a column's elements are stored together, selecting all the data for a given column is more efficient.
C) Consider our authors table in the books database: first last
Id
1 Paul Deitel
2 Harvey Deitel
3 Abbey Deitel
4 Dan Quirk
5 Alexander Wald
If we consider each row as a Python tuple, the rows would be represented as (1, 'Paul', 'Deitel') , (2, 'Harvey', 'Deitel') , etc. In a columnar database, all the values for a given column would be stored together, as in (1, 2, 3, 4, 5) , ('Paul', 'Harvey', 'Abbey', 'Dan', 'Alexander') and ('Deitel', 'Deitel', 'Deitel', 'Quirk', 'Wald') .
D) All of the above statements are true.