A) "Just as a skilled rider is said to become part of his horse, a skilled oarsman must become part of his boat"

In order to understand or achieve something, you must be able to think more deeply on what you need.  For example, the rider must understand the horse in order to ride it. The oarsman must understand how to use a boat before sailing.

what passage

explanation:

now, of course, the quality and the seasonability of these winter dreams varied, but the stuff of them remained.   they persuaded dexter several years later to pass up a business course at the state university—his father, prospering now, would have paid his way—for the precarious advantage of attending an older and more famous university in the east, where he was bothered by his scanty funds. but do not get the impression, because his winter dreams happened to be concerned at first with musings on the rich, that there was anything merely snobbish in the boy. he wanted not association with glittering things and glittering people—he wanted the glittering things themselves. often he reached out for the best without knowing why he wanted it—and sometimes he ran up against the mysterious denials and prohibitions in which life indulges.

there you go thats what we are missing