Final answer:
To control ad frequencies across multiple insertion orders, the utilization of a frequency cap is essential, serving as a tool to prevent overexposure and maintain campaign effectiveness.
Step-by-step explanation:
One way to control ad frequencies across multiple insertion orders is by using a frequency cap. This method limits the number of times an ad is shown to the same user, ensuring a wider reach and preventing audience fatigue. A frequency cap can be set at various levels, such as per ad, per campaign, or across multiple campaigns, to maintain a balanced advertising presence.