WHICH_OF_THE_FOLLOWING_IS_A_TRIANGULAR_NUMBER_SERIES_:?$

1.	WHICH_OF_THE_FOLLOWING_IS_A_TRIANGULAR_NUMBER_SERIES_:?$
A.	1, 3, 6, 9, 12, 15‚Äö√Ñ√∂‚àö√ë¬¨‚àÇ..
B.	1, 3, 6, 10, 15, 21‚Äö√Ñ√∂‚àö√ë¬¨‚àÇ‚Äö√Ñ√∂‚àö√ë¬¨‚àÇ
C.	1, 6, 12, 18, 24‚Äö√Ñ√∂‚àö√ë¬¨‚àÇ..
D.	none of the mentioned
Answer» C. 1, 6, 12, 18, 24‚Äö√Ñ√∂‚àö√ë¬¨‚àÇ..

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