Answer: Mechanical
Explanation: I spent most of my career in __Mechanical__ Engineering, designing robotics & involved in automation projects. It gets me out of my office, hands on work, dealing with all levels of people in the organization, constantly changing, a genuine sense of accomplishment of getting new products made or new machines/processes installed.
Mechanical engineering as an engineering discipline centers on building technologies that solve human needs through the application of principles (of motion, energy and force) and problem-solving techniques of engineering. This could range from designing robotics to manufacturing of automated machines. It is aimed at producing worthy engineers that ensure that designs function safely, efficiently, and reliably. If one enjoys the outdoors, hands on work, dealing with all levels of people in an organization, a constantly changing field that provides a genuine sense of accomplishment of getting new products made or new machines/processes installed, then Mechanical engineering is a great choice.