Now many manufacturers build their business reputations by enclosing ______ in the new products in case of damage in shipment or by incorrect operation. A: categories B: accessories C: analogies D: observatories

Now many manufacturers build their business reputations by enclosing ______ in the new products in case of damage in shipment or by incorrect operation. A: categories B: accessories C: C. analogies D: D. observatories