If the variance $$\sigma _x^2$$ of d(n) = x(n) - x(n - 1) is one-tenth the variance $$\sigma _x^2$$ of a stationary zero-mean discrete-time signal x(n), then the normalized autocorrelation function $$\frac{{{R_{xx}}\left( K \right)}}{{\sigma _x^2}}$$  at K = 1 is

A. True B. False

A. Space diversity B. Frequency diversity C. Broad band antenna D. Directional antenna

A. A double-tuned amplifier B. A high gain D.C. amplifier C. A cathode follower stage D. None of the above

A. Filter method B. Phase cancellation method C. Good attenuation characteristics D. All of the above