Elizabeth listened, standing there for a good three seconds or so before reacting. It wasn't that she was slow, only that there were no external indications of what was going on internally. There were different scenarios being theoretically mapped out, probabilities calculated and potential responses to them plotted. After those few seconds had passed, she turned to the vehicle, then... Looked back at Marcus.
Part of the group. He might ask questions. She needed a plausible excuse to still appear human.
So, fishing out device they all possessed for posting on the network, she made it look as if she had somehow re-routed control through that and pressed some buttons. The only possible flaw in her scheme was that her awareness of his past with Skynet had not been explained.
Above them, the tank started to move, again. Turning back on its original patrol route.
"As you wish," she spoke, then did likewise and started moving back in the direction they had just come from. "Your assistance was useful, Marcus. We should head back. Steve needs what we recovered."