If log 27 = 1.431, then the value of log 9 is:

Answer: Option C

$$\begin{array}{rl}& \log 27=1.431\\ & \Rightarrow \log \left(3^3\right)=1.431\\ & \Rightarrow 3\log 3=1.431\\ & \Rightarrow \log 3=0.477\\ & \therefore \log 9=\log \left(3^2\right)\\ & =2\log 3\\ & =2\times 0.477\\ & =0.954\end{array}$$