Which of the following can be used as assessment strategy to encourage…

An assessment strategy counts as "interdisciplinary" when it requires the learner to apply Mathematics together with another subject or a real-world context, rather than testing mathematical content in isolation. Activity-based, real-life tasks, such as project work and field-based investigations, naturally draw in other subjects like measurement, data handling, planning, geography and environmental studies, while purely observational or single-subject tools do not.

Projects and field trips both push a learner to use Mathematics, such as measurement, data collection, calculation and budgeting, while working on a task or in a setting that spans other disciplines: for example, surveying a local market, planning a trip's budget, or mapping distances during a visit. Assessing the mathematical work embedded in these tasks is therefore a genuine interdisciplinary assessment strategy.

• Anecdotal records are descriptive notes a teacher keeps on a student's day-to-day behaviour and effort during a lesson; the tool itself does not require applying Mathematics alongside another subject or a real-world context, whatever activity it is paired with.

• An Olympiad is a competitive test of mathematical content and problem-solving skill in a single-subject, timed format; it re-assesses Mathematics on its own and does not bridge the subject to any other discipline.

Since only Projects and Field trips inherently require applying Mathematics alongside another subject or a real-world context, they are the strategies that encourage interdisciplinarity.