As you are looking for CTET entrance exam answer key which held in sept 2015, so on your demand I am providing same:

CTET SEP-2015 ANSWER KEY
Set :- Q PAPER-1 MAIN
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| QNO ANS | QNO ANS | QNO ANS | QNO ANS |
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| 1 2 | 26 1 | 51 4 | 76 4 |
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| 2 1 | 27 3 | 52 4 | 77 4 |
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| 3 1 | 28 1 | 53 3 | 78 4 |
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| 4 2 | 29 3 | 54 2 | 79 2 |
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| 5 3 | 30 1 | 55 4 | 80 4 |
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| 6 2 | 31 3 | 56 1 | 81 2 |
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| 7 1 | 32 4 | 57 4 | 82 2 |
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| 8 3 | 33 3 | 58 3 | 83 2 |
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| 9 2 | 34 3 | 59 3 | 84 3 |
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| 10 2 | 35 4 | 60 4 | 85 4 |
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| 11 3 | 36 4 | 61 1 | 86 4 |
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| 12 3 | 37 2 | 62 1 | 87 2 |
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| 13 1 | 38 3 | 63 4 | 88 4,3|
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| 14 1 | 39 1 | 64 4 | 89 2 |
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| 15 4 | 40 3 | 65 3 | 90 3 |
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| 16 2 | 41 2 | 66 2 | |
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| 17 1 | 42 3 | 67 2 | |
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| 18 1 | 43 4 | 68 2 | |
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| 19 1 | 44 3 | 69 4 | |
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| 20 2 | 45 1 | 70 1 | |
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| 21 4 | 46 2 | 71 3 | |
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| 22 3 | 47 1 | 72 3 | |
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| 23 3 | 48 1 | 73 3 | |
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| 24 2 | 49 4 | 74 4 | |
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| 25 3 | 50 4 | 75 3 | |

CTET Sept Answer Key 1st paper