A run chart and a control chart are similar in that both display data over time, making it possible to observe trends, shifts, or recurring patterns in a process. The key difference is that a control chart includes control limits, or constraints, that define the expected range of normal variation for the process. These limits help analysts determine whether the process is statistically stable or whether unusual variation may signal a problem that requires attention. A run chart does not include those control boundaries; it simply displays the values in time order. Because of this, the correct description is that the two charts are essentially the same in structure, except a control chart includes limits or constraints that a process should not exceed. The options that describe one as a snapshot in time are incorrect because both are time-based charts. Therefore, the correct answer is the option identifying the control chart as the version that adds limits or thresholds for process monitoring.