When egg is not fertilised, the thick lining of the uterus breaks and comes out through the vagina as blood and mucous.
Menstruation takes place
When egg is not fertilised menstruation takes place where there is removal of unfertilised egg with blood from the body through uterus
When the egg is not fertilised the lining of the uterus wall breaks and released by the vagina in the form of mucus and blood which is also known as fertilisation.
No ur answer is wrong …the right answer is … when the egg is not fertilised the lining of uterus wall breaks and it is released in the form of blood and mucus by the vagina which process is termed as menstruation