Is This the Reason Obama Said 'No' to the Keystone Pipeline?

In rejecting the Keystone XL pipeline project this past week, the Obama administration did exactly what they told everyone they were going to do.

The question many are asking is, "Why?"

Why did the President kill the pipeline deal that so many Democrats, Republicans and labor union leaders support?

Was it done because:

A. - As the administration has said publicly, there is not enough time to do a proper environmental impact study?

B. - Thanks to alternative energy companies like Solyndra, we're on the path to becoming an oil-free energy generating country?

C. - Billionaire Warren Buffett (and Obama advisor) has an investment in a Canadian railway that would benefit from killing Keystone?

D. - Is it because Brazil, the country whose deep-water oil fields we agreed to fund, is going to be selling us cheap and plentiful oil?

In the case of the environmental impact study argument, it has been noted that the project could begin moving forward and jobs be created as another study commenced. If the findings show that the pipeline's route needed to be changed, or additional safety measures put in place, those could easily be added to the project.

The Solyndra question answers itself.

Concerning the Warren Buffett investment, Bloomberg News reports:

Warren Buffett’s Burlington Northern Santa Fe LLC is among U.S. and Canadian railroads that stand to benefit from the Obama administration’s decision to reject TransCanada Corp. (TRP)’s Keystone XL oil pipeline permit.

But what about Brazil? Was the real reason that President Obama rejected the Keystone XL deal because he was expecting Brazil to start selling us some of the cheap oil from their newly-discovered oil deep water oil fields. Estimates of the underwater fields could make Brazil an energy superpower and a very wealthy nation.

In May of 2011, President Obama visited Brazil and pledged massive financial support from America in the amount of $2 billion dollars. Obama also hinted that the money being lent to Brazil should also put America at the front of the line once the oil starts pumping.

The President's wishful thinking seems to have been undercut by China's forceful negotiating.

Last week it was announced that Brazil and China had inked a deal for oil sales, big oil sales.

Additionally, in the wake of the Keystone XL rejection, Canada's Prime Minister has talked about building a pipeline to his country's west coast where oil could easily be pumped into tankers waiting to take the oil to China:

Prime Minister Stephen Harper, in a telephone call yesterday, told Obama “Canada will continue to work to diversify its energy exports.”

If you wonder what the Prime Minster means when he says "diversify its energy exports", he is apparently talking about China. The Bloomberg News report continues:

Canada this month began hearings on a proposed pipeline by Enbridge Inc. to move crude from Alberta’s oil sands to British Columbia’s coast, where it could be shipped to Asian markets.

As the Iranians inch closer to realizing their threat to block the transport of oil through the Strait of Hormuz and the EU has voted to ban oil imports from Iran, the importance of oil from South American oil is obvious.

Some might argue that the oil underneath American soil and American waters would bring great independence and security.

So why did Obama block Keystone? Is it one of the above? What's your opinion?