Will Christians enter Hellfire, and how can this question be answered in a way that is not offensive?

The judgment of Paradise and Hell belongs to Allah alone. Muslims are obliged to invite the People of the Book to the word of Tawhid (monotheism), which is belief in Allah alone and belief in all His books and messengers, the last of whom is Muhammad (peace be upon him). Whoever disbelieves in some of the messengers or associates partners with Allah is truly a disbeliever and his destiny is Hellfire. Christians disbelieve in Muhammad and the Quran, and they associate partners with Allah by claiming a son and the Trinity. This is among the greatest forms of disbelief and polytheism, and it necessitates Hellfire for them. The invitation to Christians should be by informing them of the truth of Islam and its necessity for their salvation from Hellfire.