The factor which contributed most to the development of rival political parties in England is; Choice C: Conflicts between Catholics and Protestants about the appointment of a prime minister
During the great plague of England, The King, Charles II and his Court left London and fled to Oxford. Those people who could sent their families away from London during these months, but the poor had no recourse but to stay.
Afterwards, Conflicts between Catholics and Protestants about the appointment of a prime minister was the major factor that contributed to the development of rival political parties in England.
Read more on English politics;
https://brainly.com/question/9266801