2. From .1 to Э these nine natural numbers, select two, separately as the logarithm's number and base, to get different logarithmic values ( ).
(A) 52
(B) 53
(C) 57
(D) 72
2. (B).

Since the base is not 1, the logarithm and the base cannot take the same value, so only 64 different logarithmic forms can be taken. Among them, there are 8 cases where the true value is 1, all taking the value 0. In addition,
$$
\begin{array}{ll}
\log _{2} 3=\log _{4} 9 & \log _{2} 4=\log _{3} 9, \\
\log _{3} 2=\log _{9} 4 & \log _{4} 2=\log _{9} 3 .
\end{array}
$$

Therefore, the total number of different logarithmic values is $64-7-4=53$.