A nursing instructor is teaching a group of nursing students about antihistamines. Which statement by a student indicates an understanding of the mechanism of action of the antihistamines?

"Antihistamines block release of histamine from mast cells and basophils."

"Antihistamines block H1 receptors to prevent actions of histamine at these sites."

"H1 antagonists can bind to H1 receptors, H2 receptors, and muscarinic receptors."

"First-generation antihistamines are more selective than second-generation antihistamines."