APA Format includes: Citations, In-text Citations, Page formatting (margins, paragraphing, titles, subtitles, headers and footers, pagination, font).
IB does not care what style of formatting you use as long as everything is done consistently (the same each time) and completely (all necessary information provided to locate sources of information and avoid plagiarism). APA formatting is generally used in Psychology, Biology, Chemistry, and Physics (sometimes in ESS, Mathematics, ITGS & Computer Science).
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