Comprehensive Waste Management (CWM) provides trash hauling services for several communities in southern California. When a new client wants to establish service, the client calls the company's main office on the phone. A CWM employee collects the following information from the client: name, street address, city, state, ZIP code, area code, telephone number, e-mail address. The employee gives the new client information regarding regular weekly service dates, special services provided by the company, fees and billing procedures. CWM bills its clients every two months in advance of the service: for example, bills are sent to clients at the beginning of January for the months of January and February. Initially, CWM does all its billing manually: they send out paper bills and collect payment from clients via check. Once service is established, a client can create an online account: the online account provides an option for paperless billing and a separate option for charging a credit card rather than paying with a mailed check. To create an online account, the client creates login credentials (user name and password): they provide their CWM account number (provided on the invoice) and relevant credit card data (type of card, name, billing address, and security code). CWM's database uses the account number to look up the client's original information, then merges the new information with it. How many data stores will be shown in CWM's Level Zero data flow diagram? Zero, since all the information is stored electronically One, labeled "client database" Two, labeled "client database" and "invoice database" More than two