GATE Electrical Engineering (EE) 2018 Solved Paper

If the output signal is a scalar multiple of input signal, the signal is refereed as an eigen function (or characteristic function) and the multiplier is referred as an eigen value (or characteristic value).
If 𝑥(𝑡) is the eigen function and 𝑘 is the eigen value, then output, y(t) = kx(t).
Hence, the correct option is (A).