Read the text and answer the question.
Jaap Haartsen was born on February 13, 1963. He obtained his master's and doctoral degrees in electrical engineering at Delft University of Technology. He started the project that brought fame to his name with Ericsson in 1993. He played an active role in the creation and worldwide regulatory approval of Bluetooth technology. Haartsen then served as the SIG air protocol specification group's chairman from 1998 until 2000. He moved to Plantronics when he was 49 years old and he has worked there as a wireless systems expert. He has also served at the University of Twente.
How old was Jaap Haartsen when he became an executive?
A
Thirty years old.
B
Thirty-five years old.
C
Thirty-eight years old.
D
Forty-five years old.
E
Forty nine years old.