Consider a discrete time signal given by\(x\left[ n \right] = {\rm{\;}}{\left( { - 0.25} \right)^n}{\rm{\;}}u\left[ n \right]{\rm{\;}} + {\rm{\;}}{\left( {0.5} \right)^n}{\rm{\;}}u\left[ { - n - 1} \right]\)The region of convergence of its Z – transform would be

• A. The region inside the circle of radius 0.5 and cantered at origin
• B. the region outside the circle of radius 0.25 and centred at origin
• C. the angular region between the two circles, both centred at origin and having radii 0.25 and 0.5
• D. The entire Z plane