ANS:B - vapour is enriched with high boilers.

In the rectifying section of a continuous distillation column:

• The vapor is enriched with low boilers.

The rectifying section, also known as the stripping section or the enriching section, is where the separation of components in the feedstock occurs. In this section, the vapor rises through the column, and as it ascends, it becomes enriched with the lighter, lower boiling point components of the feed mixture. This enrichment occurs because the rising vapor preferentially contains the more volatile components, which have lower boiling points. So, in the rectifying section, the vapor is indeed enriched with low boilers, while the liquid phase becomes richer in the higher boiling point components. Therefore, the correct statement is: "In the rectifying section of a continuous distillation column, the vapor is enriched with low boilers."