Controlling pH is crucial for the survival of living organisms because even small pH variations can cause changes in enzyme shape and loss of funct...

Controlling pH is crucial for the survival of living organisms because even small pH variations can cause changes in enzyme shape and loss of function. (Atkins, P. W.; Jones, L. Princípios de Química: Questionando a Vida Moderna e o Meio Ambiente. Ed. 5, Bookman, 2011). Therefore, choose the correct alternative:

Controlling pH is crucial for the survival of living organisms because even small pH variations can cause changes in enzyme shape and loss of function.
All anions produce basic solutions in aqueous solution due to water hydrolysis.
In calculating the pH of very dilute solutions of strong acids, water autoionization can be disregarded.
Buffer systems are usually more efficient when they have equimolar concentrations of weak acid and conjugate base.
The pH of a solution of any diprotic acid can be exactly obtained by considering only the first ionization.
Buffer solutions are formed by any acid or base that is in contact with salts containing them.