Prior to the reformation, the catholic church began a practice of selling indulgences. what were indulgences?

a. churchgoers were required to attend church two days per week in order to get into heaven.
b. if money was paid to the church, one's sins would be pardoned and their time in purgatory would be reduced.
c. people could eat meat on fridays if they paid money to the church.
d. there was no such practice of selling indulgences.