If [tex]\rm s_n =\frac{( - 1) {}^{n} }{ {2}^{n} + 3} [/tex] and [tex]\rm t_n =\frac{( - 1) {}^{n} }{ 4{n} - 1} [/tex], n=0,1,2,...., then

[tex] \rm(A) \sum^{ \infty }_{n = 0} s_n \: is \: absolutely \: convergent \\ [/tex]
[tex] \rm( B) \sum^{ \infty }_{n = 0} s_n \: is \: conditionally \: convergent \\ [/tex]
[tex] \rm( C) \sum^{ \infty }_{n = 0} t_n \: is \: conditionally \: convergent \\ [/tex]
[tex] \rm(D) \sum^{ \infty }_{n = 0} t_n \: is \: absolutely \: convergent \\ [/tex]

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