Study the given pattern carefully and select the number that can replace the question mark [?] in it. First row: 6, 5, 191 Second row: 9, 7, 680 Third row: 4, 5, [?] (NOTE: Operations should be performed on the whole numbers, without breaking down the number into its constituent digits. For example, 13 - Operations on 13 such as adding/deleting/multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)