Oracle 18c

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WITH t( xml ) AS
(
 SELECT XMLType('<application xmlns="http://www.abcxyz.com/Schema/FCX/1" 
                     xmlns:xs="http://www.w3.org/2001/XMLSchema-instance">
                     <client>
                        <clientSource>
                          <amount>25000.0</amount>
                          <clientSourceType>1</clientSourceType>
                          <description>aasdadsf</description>
                        </clientSource>
                        <clientSource>
                          <amount>25000.0</amount>
                          <clientSourceType>6</clientSourceType>
                          <description>wrewertwerewrt</description>
                        </clientSource>
                        <clientSource>
                          <amount>50000.0</amount>
                          <clientSourceType>10</clientSourceType>
                          <description>second and thirs</description>
                        </clientSource>
                    </client>
                 </application>')
   FROM dual
)
SELECT "clientSourceType", "clientSourceAmount"
  FROM t,
  XMLTABLE( XMLNAMESPACES( DEFAULT 'http://www.abcxyz.com/Schema/FCX/1' ),
          '/application/client/clientSource'
      PASSING xml
      COLUMNS 
             "clientSourceType"   INT PATH 'clientSourceType',
             "clientSourceAmount" INT PATH 'amount'
         )

clientSourceType	clientSourceAmount
1	25000
6	25000
10	50000