You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
European_Union_law

Context:
The Social Charter was subsequently adopted in 1989 by 11 of the then 12 member states. The UK refused to sign the Social Charter and was exempt from the legislation covering Social Charter issues unless it agreed to be bound by the legislation. The UK subsequently was the only member state to veto the Social Charter being included as the "Social Chapter" of the 1992 Maastricht Treaty - instead, an Agreement on Social Policy was added as a protocol. Again, the UK was exempt from legislation arising from the protocol, unless it agreed to be bound by it. The protocol was to become known as "Social Chapter", despite not actually being a chapter of the Maastricht Treaty. To achieve aims of the Agreement on Social Policy the European Union was to "support and complement" the policies of member states. The aims of the Agreement on Social Policy are:

Question:
Which member state declined to sign the Social Charter?

The UK