The statements you've mentioned regarding belief in monotheism, particularly focusing on Jesus as the Son and incarnation of God, are characteristic of early Christians.
- Buddhists do not believe in a monotheistic god and do not see Jesus in this way.
- Zoroastrians have a dualistic belief system centered around Ahura Mazda, the one god, but do not consider Jesus to be divine in the same way as Christians do.
- Muslims believe in one God (Allah) and regard Jesus (Isa) as a prophet, not as the Son of God or as divine.
Thus, the correct answer would be Christians.