This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Physiological Changes of Pregnancy, Subject name: Gynaecology & Obstetrics
Which of the following is not one of the phases of Implantation of Embryo? 
Select and explain. 
A. Epithelialization, B. Apposition, C. Adhesion, D. Invasion
A: Epithelialization
Answer: A: Epithelialization 
Explanation: Implantation of Embryo can be divided into three phases: Apposition--initial contact of the blastocyst to the uterine wall Adhesion--increased physical contact between the blastocyst and decidua; and Invasion--penetration and invasion of syncytiotrophoblast and cytotrophoblast into decidua , inner third of the myometrium, and uterine vasculature.