Write the next sentence in this paragraph:

There's an optometrist seated with his patient in front of a phoropter in his clinic, talking about contact lenses and its maintenance. he

Pick your answer from:
(I). shows off the mechanics of a plastic desktop.;
(II). shows a ceramic-like glass object that looks like the design featured on the nike business logo.;
(III). touches the thing, puts a plate, then rubs a clear patch across the eyelid of the telephone receiver in a landline manner.;
(IV). explains what are the correct ways to put on contact lenses and also how to keep them clean.;
(IV).