Which of the following best describes tachypnea?

Tachypnea is characterized by rapid and shallow breathing. This term specifically refers to an increased respiratory rate often defined as more than 20 breaths per minute in adults, and can be a response to various physiological conditions such as exercise, anxiety, fever, or respiratory illnesses.

In the context of respiratory function, rapid breathing can indicate that the body is attempting to increase oxygen intake or to facilitate the removal of carbon dioxide due to underlying health issues. Knowing this distinction is crucial in assessing a patient's respiratory status, especially in clinical settings.

The other options describe different respiratory conditions: a normal respiratory rate at rest refers to eupnea, difficult breathing while sleeping is typically associated with conditions like sleep apnea, and slow and labored breathing is characterized as bradypnea or possibly dyspnea if it's indicative of distress. Understanding these terms enhances the appreciation of normal versus abnormal respiratory patterns.