Which of the following activities may be considered a "traffic building" tactic?

Offering free samples of products is a highly effective traffic building tactic because it actively engages potential visitors and draws them to an exhibitor's booth. Free samples create an incentive for attendees to stop by, allowing the company to showcase its offerings and foster personal interaction. This tactic not only attracts foot traffic but also encourages visitors to spend time at the booth, leading to more meaningful conversations and a greater chance of converting interest into sales.

The other options do not encourage visitor engagement or traffic. Limiting conversations with visitors would decrease interaction and potentially reduce interest in the booth. Removing marketing materials can lead to a lack of information available to attendees, which is counterproductive when trying to attract them. Providing only electronic brochures may limit accessibility for some visitors who prefer physical materials, thus potentially diminishing the overall effectiveness of the booth in drawing in traffic.