Which statement is true about SQL query processing in an Oracle database instance? (Choose the best answer.) 

Answer options:

A. During parsing, a SQL statement containing literals in the WHERE clause that has been executed by any session and which is cached in memory, is always reused for the current execution.
B. During execution, the Oracle server may read data from storage if the required data is not already in memory.
C. During row source generation, rows that satisfy the query are retrieved from the database and stored in memory.
D. During optimization, execution plans are formulated based on the statistics gathered by the database instance, and the lowest cost plan is selected for execution.

B