Joe is a computer service technician. People in his neighborhood usually depend on his suggestions for purchasing any computer accessory or hardware, as they believe that he has access to far more information on computer technology than the average consumer. The neighbors are also aware that Joe has the required knowledge and background for understanding the technical properties of the products. Within this context, Joe can be called a(n) ________.

A. transactional leader
B. opinion leader
C. role model
D. gate-keeper
E. international marketer