1. The problem asks to determine which figure continues the series: $f$, $x$, $?$. 2. Since the series is symbolic and visual, we analyze the pattern between $f$ and $x$. 3. The letter $f$ is followed by $x$, which are distinct letters without a clear alphabetical or geometric progression. 4. The options include three handwritten symbols and an option "Either of the figures". 5. Without the exact images, the best logical choice is "Either of the figures" since the series does not provide a clear pattern to exclude any option. Final answer: Either of the figures