Since it’s an interview it’s best to show your knowledge of the concept and explain the whole process as the conversion funnel, before getting too tactical with recommendations.
If the goal is to 3x I would explain that there are many paths you can take, and that you would prioritize the lowest hanging fruit opportunities. Is the simplest path to 3x traffic? Or could you focus in on increasing conversion rates from lead to opportunity, or opportunity to new customer. The reality is you’d probably end up doing a combination of many things, and I would offer a few examples of well thought out strategies. (Quality over quantity)
Hope it goes well!