“Justify” — what the examiner wants
How to answer a Cambridge Computer Science question that starts with Justify (9618): Cambridge's definition, what a full-mark answer contains, the mistake that loses the mark, and how often the word has come up in 27 current-syllabus past-paper questions.
Cambridge's definition
“support a case with evidence / argument”
What earns full marks
Give the reasons that support the choice or statement — specific, technical reasons tied to the scenario.
What loses the mark
Restating the choice ("a stack is best because it is a stack").
A question that uses it
Justify the use of a stack when evaluating a Reverse Polish expression.
In real past papers
Current-syllabus questions only (2210 / 0478 from 2023, 9618 from 2021); a question set under both 2210 and 0478 counts once.
27
questions
28
parts open with it
2
median marks a part
By paper
- 2210 / 0478 Paper 13 of 210 questions · 1%
- 9618 Paper 114 of 270 questions · 5%
- 9618 Paper 27 of 251 questions · 3%
- 9618 Paper 33 of 353 questions · 1%
Typical marks per part: 2 marks (57%), 3 marks (36%), 1 mark (4%), 4 marks (4%).
Topics where “Justify” comes up most
- AS LevelCommunication6 questions
- AS LevelProgramming6 questions
- AS LevelHardware4 questions
- A2 LevelData Representation2 questions
- AS LevelInformation Representation2 questions
- O Level / IGCSEHardware2 questions
- A2 LevelComputational Thinking and Problem-Solving1 question
- AS LevelData Types and Structures1 question
Recent questions that use it
Open any one to read it and mark your answer against the official mark scheme.
Marks shown as “a / b”: a = marks in parts that open with “Justify”, b = the whole question.
Don't confuse it with
- Evaluate“judge or calculate the quality, importance, amount, or value of something”4–8 marks
- Assess“make an informed judgement”3–6 marks
- Discuss“write about issue(s) or topic(s) in depth in a structured way”4–8 marks
- Comment“give an informed opinion”1–3 marks
- Suggest“apply knowledge and understanding to situations where there are a range of valid responses in order to make proposals / put forward considerations”1–2 marks per point
- Predict“suggest what may happen based on available information”1–2 marks
The definition follows the command-word table in the Cambridge syllabus; the guidance is ZAK's. Statistics come from the real past-paper question bank (command words are read from each question's wording). Command words and past papers are © Cambridge Assessment International Education.