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: Medicine
Investigation of choice of hyper-prolactinemia: 
Select and explain. 
A. TRH estimation, B. LH estimation, C. Prolactin estimation, D. Estradiol estimation
C: Prolactin estimation
Answer: C: Prolactin estimation 
Explanation: Answer is C (Prolactin estimation): Basal fasting morning prolactin levels should be measured to assess hypersecretion - Harrison