Throughput Costing.

Dear Johh,

How are you?
I hope you are doing well,
In Kaplan study text it’s mentioned the following,
the total factory cost is the fixed production cost including labor.
the total factor cost may be referred to as Operating expenses these are production/factory costs only. in the exam watch if question include costs not related to production (e.g Marketing) which wouldn’t be included in the ratio.
My question is as follow,?
Could you tell me what are the kind of costs which we should consider as a production costs?
as known most of costs are classified according to the business activity.

Thanks and regards,