394.Which of the following statements is true regarding the initialization parameter DIAGNOSTIC_DEST? The default value is the value of the environment variable $ORACLE_HOME; if $ORACLE_HOME isn't set,
A.then the default is set to $ORACLE_BASE. The default value is the value of the environment variable $ORACLE_BASE; if $ORACLE_BASE isn't set,
B.then it is set to $ORACLE_HOME.
C.DIAGNOSTIC_DEST is always equal to $ORACLE_HOME.
D.DIAGNOSTIC_DEST is always equal to $ORACLE_BASE.
正确答案是B