单项选择题

You find this query being used in your Oracle 12c datab……

You find this query being used in your Oracle 12c database:
Which method a used by the optimizer to limit the rows being returned?（）

A. A filter is added to the table query dynamically using ROWNUM to limit the rows to 20 percent of the total rows
B. All the rows are returned to the client or middle tier but only the first 20 percent are returned to the screen or the application.
C. A view is created during execution and a filter on the view limits the rows to 20 percent of the total rows.
D. A TOP-N query is created to limit the rows to 20 percent of the total rows

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