This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Dopamine acts on D2 receptors that have an inhibitory effect on prolactin secretion. Now if D2 receptors are blocked, which of the following effects will not be seen: 
Select and explain. 
A. Visual disturbance, B. Gonadal dysfunction, C. Headache, D. Excessive lactation
A: Visual disturbance
Answer: A: Visual disturbance 
Explanation: None