Which condition determines the causality of the LTI system in terms of its impulse response?
1
Only if the value of an impulse response is zero for all negative values of time
2
Only if the value of an impulse response is unity for all negative values of time
3
Only if the value of an impulse response is infinity for all negative values of time
4
Only if the value of an impulse response is negative for all negative values of time