This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Anatomy
False regarding Primary hyperparathyroidism is 
Select and explain. 
A. Most cases are sporadic, B. It is the earliest and most common manifestation of MEN1 syndrome, C. Autosomal recessive inheritance seen in association with MEN syndrome, D. 80% cases due to enlargement of a single gland or parathyroid adenoma
C: Autosomal recessive inheritance seen in association with MEN syndrome
Answer: C: Autosomal recessive inheritance seen in association with MEN syndrome 
Explanation: PHPT results from the enlargement of a single gland or parathyroid adenoma in approximately 80% of cases, multiple adenomas or hyperplasia in 15% to 20% of patients, and parathyroid carcinoma in 1% of patients. Most cases of PHPT are sporadic. It also occurs within the spectrum of a number of inherited disorders such as MEN1, MEN2A, isolated familial HPT, and familial HPT with jaw-tumour syndrome. All of these syndromes are inherited in an autosomal dominant fashion. PHPT is the earliest and most common manifestation of MEN1 and develops in 80% to 100% of patients by age 40 years old.