don't be tricked by the picture, it was the only photo I could pin to. A HUGE list of the differences between Christianity and Jehovah's witnesses with the Scriptures that support the Christian view. If they hand you literature, you could give this printable sheet to them.
The Church of Jesus Christ of Latter Day Saints (LDS) claims to be the true Christian church. The LDS church does not like being referred to as a cult,1 but they are a cult because their teachings differ significantly from historic Christian theology. This page explains what specific LDS doctrines make the LDS church a cult. As you will see, these differences are not merely minor changes in theology, but major disagreements about the nature of God, Jesus Christ, and mankind.