A. The Father made a decision to save me through what his Son paid on the cross. So my assurance of salvation is based on the fact that my faith and life has been changed.
B. I made a decision to accept the payment made by Jesus the Son on the cross. So my assurance of salvation is based on the fact that because I have put my trust in Jesus, I can be sure I am saved.
C. The Son of God is the light of love that continually (imperfect continuous) comes into the world (John 1:9) for all people. That light is fully revealed in the life, crucifixion, and resurrection of Jesus. So my assurance of salvation is based on the fact that I love that light, and expect to enjoy him in heaven for ever. Those who reject the light of God choose darkness and eternal death (John 3:19-21).
You could say that A is more common among Calvinists. B
is preached by many evangelists. C is the model offered on this
website.