Final answer:
According to Colossians 1:24, Paul's response to suffering for the cause of Christ and the Colossian believers was joy.
Step-by-step explanation:
According to Colossians 1:24, Paul's response to suffering for the cause of Christ and the Colossian believers was A) Joy.
In this verse, Paul expresses his joy in being able to suffer for Christ and his fellow believers. He sees suffering as an opportunity to share in Christ's sufferings and to further the cause of the gospel. Paul's joy in suffering demonstrates his deep faith in Christ and his commitment to spreading the message of salvation.