Read the following statements and choose the following option: 1. External nostrils lead to nasal chamber 2. Larynx is the common passage for food and air 3. During swallowing epiglottis can be covered by a thin elastic cartilaginous flap called glottis to prevent the entry of food into the larynx. 4. Trachea is a straight tube extending up to the mid-thoracic cavity, which divides at the level of 10th thoracic verte