Which sentence would be the best closing sentence in the paragraph below?
A good piano is a work of art, so it must be taken care of. It must be polished regularly and tuned at least yearly. If a piano is not
tuned, it will eventually be lower in pitch than it was originally
OA. Other instruments, such as guitars and cellos, must also be tuned regularly.
OB. Keep the lid of the piano closed to minimize dirt falling into the case.
OC. Many piano manufacturers advise against a regular furniture polish.
OD. Tuning may cost some money, but maintaining your instrument is important.