Which of the Following Will Not Produce a Buffered Solution

Which of the following will not produce a buffered solution?

A) 100 mL of 0.1 M Na₂CO₃ and 50 mL of 0.1 M HCl
B) 100 mL of 0.1 M NaHCO₃ and 25 mL of 0.2 M HCl
C) 100 mL of 0.1 M Na₂CO₃ and 75 mL of 0.2 M HCl
D) 50 mL of 0.2 M Na₂CO₃ and 5 mL of 1.0 M HCl
E) 100 mL of 0.1 M Na₂CO₃ and 50 mL of 0.1 M NaOH