Do you deny that 9/11 happened?

That's a deliberately stupid question aimed at creating the impression that your opponent is unreasonable, when the reality is you simply made this premise up yourself and are trying to attach it to your opponent. Nobody claimed 9/11 didn't happen you fallacious little cretin.

Do you deny the hijackers were Islamic & mainly from Saudi Arabia?

You have things upside down. The burden is on you to satisfactorily evidence this is true. Nobody has ever satisfactorily evidenced the planes were hijacked, period, let alone by Saudi Muslims. Many of the purported hijackers were proven not to have been involved, which means you are the one doing the denying! See:-

Hijack 'suspects' alive and well

http://news.bbc.co.uk/1/hi/world/middleeast/1559151.stm

Furthermore, and most importantly, you are IGNORING the FACT that the purported hijackers were let into the country intentionally by the US State Department!! See:-

The political journal National Review obtained the visa applications for 15 of the 19 hijackers — and evidence that all of them should have been denied entry to the country.

https://abcnews.go.com/WNT/story?id=130051&page=1

Do you deny that Osama Ben Laden took credit for the attack??

Of course I deny that. Are you retarded? He gave two public interviews in which he denied all involvement, and the video tape which the US government claims it "found" in a country the size of Texas has been thoroughly debunked by experts as a poorly constructed fake. See:-

A reason to suspect that all of the post-2001 Bin Laden tapes are fabrications is that they often appeared at times that boosted the Bush presidency or supported a claim by its chief 'war on terror' ally, British Prime Minister Tony Blair.

'The confession tape came exactly when Bush and Blair had failed to prove Bin Laden's responsibility for 9/11 and both men were trying to win international public support, particularly in the Islamic world, for the anti-terrorist campaign.

Also see:-

Prof Codevilla pointed to inconsistencies in the videos and claimed there have been no reputable sightings of Bin Laden for years (for instance, all interceptions by the West of communications made by the Al Qaeda leader suddenly ceased in late 2001).

Prof Codevilla asserted: 'The video and audio tapes alleged to be Osama's never convince the impartial observer,' he asserted. 'The guy just does not look like Osama. Some videos show him with a Semitic, aquiline nose, while others show him with a shorter, broader one. Next to that, differences between the colours and styles of his beard are small stuff.'

There are other doubters, too. Professor Bruce Lawrence, head of Duke University's religious studies' department and the foremost Bin Laden expert, argues that the increasingly secular language in the video and audio tapes of Osama (his earliest ones are littered with references to God and the Prophet Mohammed) are inconsistent with his strict Islamic religion, Wahhabism.

He notes that, on one video, Bin Laden wears golden rings on his fingers, an adornment banned among Wahhabi followers.

http://www.dailymail.co.uk/news/article-1212851/Has-Osama-Bin-Laden-dead-seven-years--U- S-Britain-covering-continue-war-terror.html

The "foremost bin Laden expert" in the world is telling you that it isn't bin Laden. Are you stupid bronto?