Consider two continuous time signals $x(t)$ and $y(t)$ as shown below
If $X(f)$ denotes the Fourier transform of $x(t)$, then the Fourier transform of $y(t)$ is $\_\_\_\_\_\_$.
- $-4 X(4 f) e^{-j \pi f}$
- $-4 X(4 f) e^{-j 4 \pi f}$
- $-\frac{1}{4} X(f / 4) e^{-j \pi f}$
- $-\frac{1}{4} X(f / 4) e^{-j 4 \pi f}$