1) Mormons believe that eternal life comes by water baptism.
Doctrines & Covenants 128:12 Herein is glory and honor, and immortality and eternal life--The ordinance of baptism by water, to be immersed therein in order to answer to the likeness of the dead, that one principle might accord with the other; to be immersed in the water and come forth out of the water is in the likeness of the resurrection of the dead in coming forth out of their graves; hence, this ordinance was instituted to form a relationship with the ordinance of baptism for the dead, being in likeness of the dead.
Correction: Eternal life is through sincere belief in and confession of Jesus Christ.
John 3:16 "For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life."
John 3:36 "He who believes in the Son has everlasting life; and he who does not believe the Son shall not see life, but the wrath of God abides on him."
John 6:47 "Most assuredly, I say to you, he who believes in Me has everlasting life."
Romans 10:8-10 But what does it say? "The word is near you, in your mouth and in your heart" (that is, the word of faith which we preach): that if you confess with your mouth the Lord Jesus and believe in your heart that God has raised Him from the dead, you will be saved. For with the heart one believes unto righteousness, and with the mouth confession is made unto salvation.
Note: Joseph Smith used baptism to promote the pagan doctrine of baptism for the dead.
2) Mormon missionaries preach baptism as the means of salvation.
Latter-day Revelation, concerning baptism and its object, shows that the same importance is ascribed by the Lord to the ordinance today as in earlier times. That there may be no question as to the application of this doctrine to the Church in the present dispensation, the principle has been restated, the law has been reenacted for our guidance. The elders of the Church are commissioned to preach the remission of sins as obtainable through the means of authorized baptism. A Study of the Articles of Faith, Talmage, page 124.
Correction: Christians will preach the person of Jesus Christ as the means of salvation.
1 Corinthians 1:17-18 For Christ did not send me to baptize, but to preach the gospel, not with wisdom of words, lest the cross of Christ should be made of no effect. For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God.
1 Corinthians 15:1-4 Moreover, brethren, I declare to you the gospel which I preached to you, which also you received and in which you stand, by which also you are saved, if you hold fast that word which I preached to you; unless you believed in vain. For I delivered to you first of all that which I also received: that Christ died for our sins according to the Scriptures, and that He was buried, and that He rose again the third day according to the Scriptures.
3) Mormons believe that admission to the church of Christ is by baptism.
The Special Purpose of Baptism is to afford admission to the Church of Christ with remission of sins. What need of more words to prove the worth of this divinely appointed ordinance? What gift could be offered the human race greater than a sure means of obtaining forgiveness for transgression? Justice forbids the granting of universal and unconditional pardon for sins committed except through obedience to ordained law; but means simple and effective are provided whereby the penitent sinner may enter into a covenant with God, sealing that covenant with the sign that commands recognition in heaven, that he will submit himself to the laws of God; thus he places himself within the reach of Mercy, under whose protecting influence he may win eternal life. A Study of the Articles of Faith, Talmage, page 121.
Correction: Admission to the true church of Jesus Christ is by sincere confession of Jesus Christ.
Matthew 16:15-18 He said to them, "But who do you say that I am?" Simon Peter answered and said, "You are the Christ, the Son of the living God." Jesus answered and said to him, "Blessed are you, Simon Bar-Jonah, for flesh and blood has not revealed this to you, but My Father who is in heaven. And I also say to you that you are Peter, and on this rock (confession) I will build My church, and the gates of Hades shall not prevail against it."