Altitude versus which? Mag or ground track?

"Journeyman" wrote in message
. ..
In article , Bob Gardner wrote:
The reg says "magnetic course," and if you successfully figured out the
appropriate wind correction, your ground track would have been the same
as
your magnetic course. Ergo, 7500.

Just be very, very careful you understand what the controller
means when he says, "squawk altitude"


Pardon my confusion but what does a controller have to do with this?