If I lay here.. If I just lay here..

Couple of days ago, through the advancement of communication technology, I received an audio clip of a teleconversation. It was between a guy and a Streamyx call center agent. And boy was the guy really pissed. It started off slow but after a while the guy was shouting, screaming and cursing. The F word used was a lot more than can be found Rumet's blog.

Anyway how would you interpret this sentence: 'lying on a plane'. Is it

a. lying on your back on an airplane
b. lying on your back on a plane (as in X-Y plane)
c. telling a lie on an airplane
d. telling a lie on a plane (as in X-Y plane)