The Optimal Item Difficulty of a Six-Alternative Test Is

question 66

Multiple Choice

The optimal item difficulty of a six-alternative test is

• A).50.
• B).585.
• C).60.
• D).625.

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Definitions:

Mesozoic Era

A geologic era that occurred about 252 to 66 million years ago, characterized by the dominance of dinosaurs and the appearance of flowering plants.

Mass Extinctions

Events in Earth's history when significant numbers of species disappear rapidly and irreversibly, often due to drastic environmental changes.

Varves

Thin, alternating light-colored and dark layers of sediment that form in lakes because of seasonal variations of deposition and biologic activity.

Ice Cores

Cylinder-shaped samples from ice sheets or glaciers that scientists study to understand past climates.