Answer the question from the given passage. Your answer should be directly extracted from the passage, and it should be a single entity, name, or number, not a sentence.

Let me give you an example: Passage: Martin Luther married Katharina von Bora, one of 12 nuns he had helped escape from the Nimbschen Cistercian convent in April 1523, when he arranged for them to be smuggled out in herring barrels. Suddenly, and while I was occupied with far different thoughts, he wrote to Wenceslaus Link, “the Lord has plunged me into marriage. At the time of their marriage, Katharina was 26 years old and Luther was 41 years old. Question: In a letter who did Luther credit for his union with Katharina?
The answer to this example can be: the Lord
Here is why: The paragraph clearly states that, Luther has credited the Lord for his union with Katharina, hence the Lord is correct answer.

OK. solve this:
Passage: As in the House of Commons, a number of qualifications apply to being an MSP. Such qualifications were introduced under the House of Commons Disqualification Act 1975 and the British Nationality Act 1981. Specifically, members must be over the age of 18 and must be a citizen of the United Kingdom, the Republic of Ireland, one of the countries in the Commonwealth of Nations, a citizen of a British overseas territory, or a European Union citizen resident in the UK. Members of the police and the armed forces are disqualified from sitting in the Scottish Parliament as elected MSPs, and similarly, civil servants and members of foreign legislatures are disqualified. An individual may not sit in the Scottish Parliament if he or she is judged to be insane under the terms of the Mental Health (Care and Treatment) (Scotland) Act 2003. Question: When was the British Nationality Act passed?
Answer:
1981