The condition for a system to be causal is
A. All poles of its transfer function must be left half of s-plane
B. All poles of its transfer function must be right half of s-plane
C. All zeros of its transfer function must be right half of s-plane
D. All zeros of its transfer function must be left half of s-plane
The interface between an analog signal and a digital processor is
A. D/A converter
B. A/D converter
C. Modulator
D. Demodulator
The speech signal is obtained after
A. Analog to digital conversion
B. Digital to analog conversion
C. Modulation
D. Quantization
Telegraph signals are examples of
A. Digital signals
B. Analog signals
C. Impulse signals
D. Pulse train
A. 1, 2 and 3 are correct
B. 1 and 2 are correct
C. 1, 2 and 4 are correct
D. All the four are correct
A. 1, 2 and 3 are correct
B. 1 and 2 are correct
C. 1 and 3 are correct
D. All the four are correct