Final answer:
The statements can be classified as argumentative or persuasive based on their characteristics and purposes.
Step-by-step explanation:
Statement a) 'It seriously presents alternative viewpoints.' best describes an argumentative approach. Argumentative writing focuses on presenting different perspectives on a topic.
Statement b) 'The approach is usually one-sided.' is more descriptive of a persuasive writing style. Persuasive essays tend to present a single viewpoint and aim to convince the reader to agree with the author.
Statement c) 'Requires ample evidence and research to be effective.' is characteristic of argumentative writing. Argumentative essays rely heavily on evidence and research to support their claims.
Statement d) 'Its primary purpose is to convince the reader to agree on the author's view.' best describes a persuasive approach. The main goal of persuasive writing is to persuade the reader to adopt the author's perspective.