In a UML sequence diagram, a lifeline is represented by a box at the top of a dashed line. The box contains the name of the lifeline and can optionally include the object name, a colon, and the class name or the type (if the lifeline represents a specific instance of a class or type).
In the provided sequence diagram, the lifeline has the following notation:
sensorDriver[x-axisGyro]: DeviceDriver
This notation includes three parts:
* sensorDriveris the name of the lifeline, which represents the identity of the participating element.
* [x-axisGyro]is a selector that specifies that the lifeline represents a specific object within a set of similar objects.
* DeviceDriveris the type of the object that the lifeline represents.
Based on this, the name of the property that the lifeline represents in the "Start Sensor Device Driver" interaction issensorDriver.
Therefore, the correct answer is:
C: sensorDriver