Given a paragraph, your job is to generate a question that can be answered from the passage. The answer to your question should be a single entity, person, time, etc. that can be extracted from the passage.

Let me give you an example: There are a million times more viruses on the planet than stars in the universe. Viruses also harbor the majority of genetic diversity on Earth. Scientists are finding evidence of viruses as a planetary force, influencing the global climate and geochemical cycles. They have also profoundly shaped the evolution of their hosts. The human genome, for example, contains 100,000 segments of virus DNA.
The answer to this example can be: How many segments of virus DNA does the human genome contain?
Here is why: The paragraph states the number of segments of virus DNA does the human genome contain, hence the question asked above is appropriate.

OK. solve this:
Following the election of the UK Labour Party to government in 1997, the UK formally subscribed to the Agreement on Social Policy, which allowed it to be included with minor amendments as the Social Chapter of the 1997 Treaty of Amsterdam. The UK subsequently adopted the main legislation previously agreed under the Agreement on Social Policy, the 1994 Works Council Directive, which required workforce consultation in businesses, and the 1996 Parental Leave Directive. In the 10 years following the 1997 Treaty of Amsterdam and adoption of the Social Chapter the European Union has undertaken policy initiatives in various social policy areas, including labour and industry relations, equal opportunity, health and safety, public health, protection of children, the disabled and elderly, poverty, migrant workers, education, training and youth.
Answer:
What lead to the UK to subscribe to the agreement on Social Policy?