The modals may in “Well it may have been” (Comment 1) and m...

Answer question according to TEXT 1 below, adapted from http://news.bbc.co.uk/2/hi/americas/8606466.stm (accessed on April 7th, 2010) .

TEXT 1

At least 200 people have died in the Brazilian state of Rio de Janeiro after another storm. This is arguably the worst torrential rain for decades, causing flooding and landslides. Our website readers in Rio de Janeiro have been sharing their experiences.

Comment 1 - I’ve never seen such chaos. We weren’t prepared for this, even though we were warned that a big storm was about to come. Newspapers are saying that the reason for the catastrophe is the garbage. Well it may have been. We need to teach recycling at schools and community groups, otherwise we will have more disasters like this. (Lia, Niterói)

Comment 2 - Today I witnessed Rio de Janeiro on the brink of collapse. I ventured out around midday, just as the electric power blacked out in my neighbourhood. Three hours later, looking out of my office window, the city still reminded me of a war zone. “What´ve we done to deserve this?”, I thought. It’s night time now and I haven’t been able to return home. I might do so tomorrow. (José, Rio)

Comment 3 - Worldwide, we are seeing more and more climate instability. The deserts of central Asia are growing, while areas of the US (and now Rio) are drenched. The lakes in Minnesota have never thawed this early, at any time in the recorded record. The icecaps will be history, and islands around the world are disappearing under the surf. The oceans are warming, the coral reefs are dying. How much more evidence do we need of global warming? (João, Brasília)