What are the components of a flat plate collector?

• A. Flat box, a plate with reflective coating and fluid circulation passageways, an opaque cover, a circulating fluid
• B. Flat box, a dark coloured plate with fluid circulation passageways, an opaque, a circulating fluid
• C. Flat box, a dark coloured plate with fluid circulation passageways, a transparent cover
• D. Flat box, a dark coloured plate fluid circulation passageways, a transparent cover, a circulating fluid