Ronke and Casey answered the question in 3 points:
1) Objective vs. Subjective claims: All religions make objective truth claims that are either true or untrue (i.e. the sky is blue; heaven/hell are real). A person's religious beliefs can't be compared to something like their favorite ice cream flavor, which is based purely on subjective preference. Therefore, one shouldn't choose to follow a certain religion just because it suits his/her lifestyle better or makes them happier, but because it's claims are actually true to reality.
2) Who is Jesus? Not all religions are the same because they say very different things about Jesus. Buddhism, Islam, and Judaism all say Jesus was just an enlightened man or a prophet, but only Christianity states that Jesus was the Son of God.
3) Do vs. Done: Most religions claim that the way to solve our problems depends on us DOING things. Buddhism says that we must reach a state of emotional numbness to overcome suffering/pain, while Islam and Judaism say that if we follow the commands of Allah/God, He will love us and save us from the bad things in the world. Christianity is the only religion that focuses on what has already been DONE to solve man's greatest problem, which is sin. The gospel says that the world is indeed full of suffering, and that suffering is caused by our sinfulness. But because Jesus died for our sins, if we choose to believe in him, we can all look forward to eternal life in heaven--a place with no more sin, death, sorrow, or pain.