Buffer solutions are designed to:

Buffer solutions are specifically formulated to maintain a relatively stable pH level even when acids or bases are introduced. This stability is achieved through the presence of weak acids and their conjugate bases (or vice versa) in the solution. When an acid or a base is added to a buffer, the weak acid will neutralize added base, and the conjugate base will neutralize added acid. This chemical reaction offsets changes to the overall pH, allowing the buffer solution to resist significant fluctuations in pH.

The option indicating that buffers change pH dramatically is incorrect since that would defeat the purpose of having a buffer. Additionally, a buffer does not need to have a pH of exactly 7; it can be designed to maintain any desired pH value, depending on the weak acid and its conjugate base that are used in its preparation. Finally, buffers can be made from weak acids and bases, not just strong ones, as strong acids and bases completely dissociate in solution and do not provide the necessary equilibrium conditions for buffering action. Thus, buffers serve a crucial role in controlling pH in various chemical systems and biological processes.