General Conditions and Home Office expenses are indirect costs. Direct cost are mostly directly related with the production.
Cost classification is very important for project cost management. You can check this resource for
direct and indirect cost
examples.
Overhead is generally an indirect cost. General conditions are typically project costs not related to actual physical work i.e fees, utilities at the site, superintendent etc. These are items I can still put against the job, whereas my overhead really cannot.
Where did get this question, so we can cite the source?
Training for Project Management Professional (PMP)®, PMI Agile Certified Practitioner (PMI-ACP)®, and Certified Associate in Project Management (CAPM)®