log x < 1 <=> 0 < x < 10; log 1/pi (x) < log 1/pi (y) <=> x>y>0

A. $\log x<1\iff 0<x<10.$

B. ${\log }_{\frac{1}{\pi }}x<{\log }_{\frac{1}{\pi }}y\iff x>y>0.$

C. $\ln x\ge 0\iff x\ge 1.$

D. ${\log }_4{x}^2>{\log }_{2}y\iff x>y>0.$