Allah's promise in the Qur'an:
“Indeed, it is We who sent down the Qur'an and indeed, We will
be its guardian.” (Q.15:9).
“Then do they not reflect upon the Qur'an? If it had been from [any]
other than Allah , they would have found within it much
contradiction.“ (Q. 4:82)
“Say, "What thing is greatest in testimony?" Say, " Allah is witness
between me and you. And this Qur'an was revealed to me that I may warn
you thereby and whomever it reaches. Do you [truly] testify that with
Allah there are other deities?" Say, "I will not testify [with you]."
Say, "Indeed, He is but one God, and indeed, I am free of what you
associate [with Him]."“ (Q. 6:19)
“And this is a Book which We have sent down, blessed and confirming
what was before it, that you may warn the Mother of Cities and those
around it. Those who believe in the Hereafter believe in it, and they
are maintaining their prayers.“ (Q. 6:92)
“And indeed, [O Muhammad], you receive the Qur'an from one Wise and
Knowing.“ (Q. 27:6)
The revelation of the Book is from Allah , the Exalted in Might, the
Wise. (Q. 45:2)
The Qur'an has been preserved in both oral and written form in a way no other book has, and with each form providing a check and balance for the authenticity of the other.
if you need some
human explanation, you can find it at this link and this
Based on comments of OP, I'd like to add it to my answer because I realized that it related.
OP said, "You're simple quoting some text written by and about one man. I could have written the same thing."
I just simple quoting because he has same arguments for Quran tafseer. I wouldn't write it again. Just simply linked to it.
OP said, "Additionally, your assertion that no other book has been preserved like the Qura'an is false. Prime example being the Torah, off of which the Qura'an is based. (as verified by discoveries like the Dead Sea Scrolls)"
About Torah, I realized and believed that it exist. If you are Muslim, you will find different how Quran preserved and Torah (generally, people of book) preserved. I'd like to add verse Q. 3:78 about it.
And indeed, there is among them a party who alter the Scripture
with their tongues so you may think it is from the Scripture, but it
is not from the Scripture. And they say, "This is from Allah ," but it
is not from Allah . And they speak untruth about Allah while they
know. (Q. 3:78)