What is the main problem in assessing students using only closed-ended…

In test-item design, closed-ended questions (MCQ, true/false, matching) restrict a student's response to one of a small, predetermined set of options, while open-ended (constructed-response) questions let the student build a free-form answer. Because the response space is fixed in advance, a closed-ended item is efficient and objective to score, but it caps how much reasoning, elaboration, or higher-order thinking (analysis, synthesis, evaluation) a student's answer can show -- the format itself sets a ceiling on the depth of what can be assessed.

Applying this to the question: if an assessment relies only on closed-ended items, every response collapses to a single selection from the given choices. A student who has a deep, well-reasoned understanding and one who merely recognizes the right label produce the same recorded answer -- there is no way for the format to capture the difference. That structural constraint on how much the answer can reveal is exactly the main problem being asked about.

Contrast with the other choices offered:

• Reduces grading time -- closed-ended items do score faster because there is one fixed key to check, but that is a scoring-efficiency benefit, not a problem the format creates.

• Promotes creativity -- closed-ended items ask the student to pick from options that are already written, so they do not invite the student to construct an original response at all.

• Improves communication skills -- communication is exercised by composing and articulating one's own answer, which selecting a pre-written option does not require.

So among the choices offered, the one that names the format's actual limitation is that it limits the depth of the answer a student can give.