A). This statement is false. In NVL2, the first expression is returned if it is not null.
B). This statement is false. NVL2 takes exactly three arguments, not any number of expressions.
C). This statement is false. COALESCE stops evaluating its list of expressions as soon as it finds the first non-null value.
D). This is true. COALESCE returns the first non-null expression in its list.
E). This statement is true. NVL requires the first and second expressions to be of the same or compatible data types because it returns the first expression if it is not null, otherwise it returns the second.
F). This statement is false. NVL takes exactly two arguments, not any number.
References:
* Oracle Documentation on COALESCE:
https://docs.oracle.com/database/121/SQLRF/functions040.htm#SQLRF00625
* Oracle Documentation on NVL:
https://docs.oracle.com/database/121/SQLRF/functions130.htm#SQLRF00683
* Oracle Documentation on NVL2:
https://docs.oracle.com/database/121/SQLRF/functions123.htm#SQLRF00682