Piling on, one of the fastest ways of doing this is to use Window Function with the appropriate POC index

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IF OBJECT_ID('tempdb..#tab1', 'U') IS NOT NULL

DROP TABLE #tab1;

CREATE TABLE #tab1

(

A INT

,B VARCHAR(10)

,C VARCHAR(10)

,D VARCHAR(10)

,E VARCHAR(10)

);

INSERT #tab1

(A, B, C, D, E)

VALUES (1, 'test', 'test0', 'test2', 'test3'),

(1, 'test1', 'test1', 'test3', 'test4'),

(1, 'test1', 'test2', 'test3', 'test5'),

(1, 'test1', 'test3', 'test3', 'test4');

CREATE NONCLUSTERED INDEX NCLIDX#tab1_A_B_D_E_INCL_C ON #tab1(A ASC, B ASC, D ASC, E ASC) INCLUDE (C);

SELECT

SD.A

,SD.B

,SD.C

,SD.D

,SD.E

,ROW_NUMBER() OVER

(

PARTITION BY SD.A

,SD.B

,SD.D

,SD.E

ORDER BY SD.A

)

FROM #tab1 SD;