Assuming you are a real pilot:
The correct answer is in the operations manual or AFM or equivalent, assuming it is stated there. If it isn't (for example, you may be flying a two-crew private operation on an aircraft with an AFM which doesn't include this, perhaps because it's a single-pilot aircraft), then you need to decide which approach works best for you. I've flown with several variations on the theme, and generally found that of those presented, option C works best, though a better method involves PNF responding to all but the most essential checklists (eg, before landing).
Either way, the response should be exactly the word or words on the checklist, for example if the checklist says 'LANDING GEAR... UP' then those are the words which should be spoken; not 'UP AND OFF' OR 'UP LIGHTS OUT' or any others. The exception is items such as 'FUEL... ____ KILOS' where, obviously, the appropriate blank should be filled.
The checklist is not a conversation.