The correct answer is: "More than a million people immigrated to Europe in 2009".
The graph only shows quantitative information about the number of immigrants that arrived to each country in 2009. If adding the immigration figures that the graph shows for each country, the total numbers exceeds one million. Only in Spain, the country that received the largest number of immigrants in 2009, 500,000 people arrived. Italy received more than 400,000 and Germany more than 300,000. Only adding up the figures of these three countries (the top 3 ones), more than a million immigrants can be counted.
Therefore, qualitative information about their preferences (such as climate) or about how hard their lives have been, cannot be inferred from this grpah.