King john agreed to sign the magna carta because of the widespread opposition to his rule among which of these groups?
a. the nobility
b. the peasants
c. the catholic church
d. all of the above

King John agreed to sign the Magna Carta because of the widespread opposition to his rule among the Nobility. The correct option among all the options given in the question is option "a". The rebellion of 1215 was the main reason behind signing of the Magna Carta. The main reason behind the rebellion was that the powerful people during that time felt that were not given enough importance and power by the King. The powerful people mainly included the Nobility.