Given the task definition and input, reply with output. In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.

Question: Which power-switching election in the 1970s had more total votes? Passage:Secretary of State for Employment and Productivity Barbara Castle introduced an Employed Persons (Health and Safety) Bill in 1970 but the debate around the Bill soon generated a belief that it did not address fundamental issues of workplace safety. In the same year, the Occupational Safety and Health Act was passed into United States federal law. As a result, a committee of inquiry chaired by Lord Robens was established towards the end of Harold Wilson's first government. When the Conservative Party came to power following the 1970 United Kingdom general election, they gave Castle's Bill no parliamentary time, preferring to wait for the Robens Report which was published in 1972. Conservative Secretary of State for Employment William Whitelaw introduced a new Bill on 28 January 1974 but Labour were returned to power in the February 1974 United Kingdom general election and the Bill again lost. The new Labour administration finally secured the passage of a Bill that year.
Links: a. February 1974 United Kingdom general election b. Alfred Robens, Baron Robens of Woldingham c. February 1974 United Kingdom general election d. 1970 United Kingdom general election
d