When first western bank sent surveys via mail to its savings accounts-only customers to ask why they did not also have checking accounts and credit cards with first western, they were gathering data. multiple choice intercept secondary observational questionnaire nonprobability

According to me the bank was gathering questionnaire data while sending surveys via mail to its savings accounts-only customers. The questionnaire method of collecting data or gathering information is the most easy and convenient way of gathering information.

Basically it is the survey research in which a set of standardized questions set for the people to get the information based or related to a certain topic. This questionnaire can be sent via post, email or by distribution.

where is your diagram?

answer; win because bill had a legal right to drink alcohol;