During swallowing, entry of food into the trachea is prevented by the

Explanation

The epiglottis is a flap of cartilage that folds back over the opening of the larynx as the larynx rises during swallowing, so the bolus is directed into the oesophagus behind it. The soft palate closes the passage to the nose at the same moment, which is why it is the tempting alternative. The glottis is the opening itself, not the structure that covers it.