Which of the following will produce a buffer sollution when mixed in equal volumes ?
A. `0.1 " mol dm"^(-3) NH_(4)OH " and " 0.1 " mol dm"^(-3) HCI`
B. `0.05 " mol dm" ^(-3) NH_(4)OH " and " 0.1 " mol dm"^(-3) HCI`
C. `0.1 " mol dm"^(-3) NH_(4)OH " and " 0.05 " mol dm"^(-3) HCI`
D. `0.1 " mol dm " ^(-3) CH_(4)COONa " and " 0.1 " mol dm" ^(-3) NaOH`