Adding bran to a bread recipe will:

When bran is added to a bread recipe, it contributes bulk and fiber but does not provide the same gluten-forming properties as flour. Gluten is essential for trapping gas produced during fermentation, which causes the dough to rise and increases the volume of the bread. The coarse texture of bran can negatively impact the dough's ability to rise by breaking the gluten strands, leading to a denser bread with reduced volume.

As a result, the correct answer highlights that adding bran will decrease the volume of the bread. Therefore, understanding the role of bran in dough formulation is key to anticipating its effect on the final product's characteristics.