What event does Pentecost commemorate in the Catholic Church?

Pentecost commemorates the descent of the Holy Spirit upon the apostles, an event that marks a significant moment in the early Christian church. This occurrence took place 50 days after Easter, celebrating the fulfillment of Jesus' promise to send the Holy Spirit as a guide and advocate. During this event, the apostles were empowered to speak in different languages, allowing them to spread the message of Jesus Christ to a diverse audience. This empowerment by the Holy Spirit is often seen as the birthday of the Church, as it catalyzed the apostles' mission to evangelize and build the Christian community.

The other options relate to important events in the Christian narrative but do not pertain to Pentecost specifically. The resurrection of Jesus symbolizes victory over sin and death; the Last Supper signifies the establishment of the Eucharist; and the crucifixion represents the sacrifice of Jesus for humanity's salvation. While all these events are central to Christian faith, they do not capture the essence of Pentecost, which is focused on the Holy Spirit's coming and its implications for believers.