Choose the correct alternatives from given ones that will complete the series. 0,9,3,7,6,?, 9, 3

This is an alternating series: 0+9=9, 9-6=3, 3+4=7, 7-1=6, 6+?=?. Looking at pairs: (0,9), (3,7), (6,?), (9,3). In each pair, second = first + 9, then first = first + 3. The pattern in pairs is: first element increases by 3 (0,3,6,9). Second elements are 9,7,?,3 which decrease by 2. So missing is 7-2 = 5. Alternatively: 0+9=9, 9-6=3, 3+4=7, 7-1=6, 6+(-1)=5 doesn't work. The alternating pattern is: add 9, subtract 6, add 4, subtract 1, add (-1)... not clean. The pair pattern works better.