\(A=\left|x-1\right|+\left|2-x\right|\ge\left|x-1+2-x\right|=1\)
\(Min_A=1\)
\(B=\left|x+1\right|+\left|x-1\right|\ge\left|x+1-x+1\right|=2\)
\(Min_B=2\)
\(C=\left|2x+3\right|+\left(y-1\right)^2-5\ge-5\)
\(Min_C=-5\)
\(E=\left(2x+3\right)^2-4\ge-4\)
\(Min_E=-4\)