The formation constant (log K1) of metal ions $^{A n+}$ , $^{B m+}$ , and $^{C p+}$ with oxygen donors in water is given below:

Metal ion OH- NO3- SO42-

An+ 5.0 2.5 1.0

Bm+ 1.0 5.5 12.0

Cp+ 0.5 7.5 14.0

Consider the following statements:

A. $^{A n +}$ is a hard acid; $^{B m+}$ is a soft acid.
B. $^{A n+}$ is a soft acid; $^{C p+}$ is a hard acid.
C. is a soft acid; Cp+ is a soft acid.