There are 20 branch offices who offer face to face banking transactions. The district manager would like to determine the customer satisfaction level for the entire organization, but also for each of the branch offices. A decision is made to ask 20 customers each week to fill out a brief survey. To help focus future efforts, the branch manager would like to also have demographic data: customer's bank account number, age (40), gender, amount of today's transaction ($x.xx format), length of time waiting in line (in minutes and to any level of detail the customer wants to offer), and additional comments about their visit. To collect gender the survey team has decided to allow the following choices: male, female, non-binary, prefer not to answer. Overall satisfaction with the visit will be 1 (not satisfied at all), 2 (not very satisfied), 3 (somewhat satisfied), 4 (satisfied), or 5 (very satisfied). The data will be collected and input into a database with three tables: customer, survey, bank data. The customer table will consist of the customer account number, their first name and last name. The survey table with a unique survey number, the survey date, the customer account number, and specific responses. The bank data which includes the customer account number their address, type of accounts they hold, and date when they became a bank member. Which variable would be the foreign key in the Survey Table? Survey Number Gender Satisfaction Rating Customer Account Number