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
A 33 year old woman has experienced episodes of fatigue, pleural effusion, pericardial effusion and carpal tunnel syndrome and macrocytic anemia. Best test for diagnosis shall be - 
Select and explain. 
A. Anti-beta 2 phospholipid antibodies, B. Anti-smith antibody, C. Antinulear antibody, D. Assay for thyroid hormones
D: Assay for thyroid hormones
Answer: D: Assay for thyroid hormones 
Explanation: ANSWER- D. Assay for thyroid hormonesCarpel tunnel syndrome is a common complication of hypothyroidism and is often reversible with thyroid hormone therapy.Normally hypothyroidism is associated with normochromic anemia but may sometimes also cause macrocytic anemia.