Keď dôjde k návšteve predajne, údaje sa overujú prostredníctvom panela používateľov, ktorí sa dobrovoľne zúčastnia na programe Odmeny za prieskumy Google. Koľko používateľov sa dobrovoľne účastní?

The correct answer is 5 million. Google's "Store Visits" measurement relies on aggregated and anonymized data from a large panel of users who have opted into Location History and participate in programs like Google Opinion Rewards. This extensive user base, estimated at around 5 million, provides the necessary scale and privacy safeguards for accurately estimating store visits without identifying individual users. The other options are significantly lower than the actual reported panel size required for this type of robust, privacy-centric measurement.