Sugars leave the source region and immediately enter into a ____, followed by direct movement into the ____.

A) pit; perforation plate
B) companion cell; sieve element
C) pit; vessel element
D) plasmodesmata; sink
E) phloem tube; companion cell

Sugars move from source cells (e.g. leaves) into companion cells, which supply them with energy for loading into sieve tubes. Once in the sieve tubes, sugars move via pressure flow to sink cells (e.g. roots) for storage or use. Vessel elements are part of the xylem and not involved in sugar transport. Plasmodesmata are channels between plant cells through which some sugars move, but not in the specific scenario described in the question.