Arrange the following contributions of Harriet Martineau in the order of their significance to the development of sociological methods: A) Documenting social practices and gender roles, B) Introducing methods of observation and sampling, C) Highlighting the complexities of social structures, D) Analyzing bias in social research.

Harriet Martineau made several important contributions to sociology that helped shape how we study society. First, she introduced methods of observation and sampling, which are crucial for gathering accurate data about social behaviors. Next, she documented social practices and gender roles, providing insights into everyday life and how these factors influence society. Following that, she highlighted the complexities of social structures, helping us understand how different parts of society interact with each other. Finally, she analyzed bias in social research, emphasizing the need for objectivity in studying social issues, which is essential for credible research.