[pinkpanther]

You can only disbelieve in the prophethood of Muhammad صلي الله عليه وسلم, but you cannot falsify the claim. 

Jesus said, according to the Gospels, that he didn't complete the message. That means he wasn't the fulfillment of divine revelation. He said that another will come after him with the complete message, the fulfillment of the divine revelation.

There is only 1 divine revelation that came after Jesus, and that is the Quran.

in John 16:12-13, Jesus says:

"I have much more to say to you, but you cannot bear it now. When he, the Spirit of truth, comes, he will guide you into all the truth."

This suggests that Jesus himself indicated that the full revelation would be completed or continued through the coming of the Holy Spirit, rather than another human prophet coming after him...so we can rule out Muhammad completely ..

We believe the Holy Spirit continues to guide us into the truth while the Quran somewhat does not show that it is capable to protrude that truth because of the lack of details..