Cables on the throttle

[mrob]

Dumb question: the transmission accelerator cable (yes, it's an auto -- mea culpa) and the accelerator cable connect to the throttle, but what's the third cable? Please see pic attached. Is Bentley incorrectly identifying this as the accelerator cable? RealOEM is no help. TIA. (car is an 88 325iX)

[parkerbink]

Cruise control?

[mr.vang]

Cruise control.

[mrob]

Thanks Mr Vang and parkerbink