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: Physiology
ABC transpoer ? 
Select and explain. 
A. P. glycoprotein, B. Membrane sparing, C. Channel, D. Adenylyl cyclase
A: P. glycoprotein
Answer: A: P. glycoprotein 
Explanation: Ans. is'a' i.e., P. glycoproteinATP-binding cassette transpoers (ABCtranspoers) are integral transmembrane proteins that utilize ATP as an energy source to translocate a variety of substrates across membranes.P-glycoprotein is an ATP-binding cassette (ABC) transpoer and is an impoant factor to limit membrane permeability in several tissues and/or elimination pathways into urine (rend tubles) and bile (liver).