In materials engineering, which scenario indicates a low likelihood but potentially high consequence?

Question

In materials engineering, which scenario indicates a  low likelihood  but potentially  high consequence ?

Answer

A predictable and slight variation in material strength from batch to batch.

Answer

Standard wear and tear of a commonly used building material.

Answer

A newly developed alloy displaying unexpected brittleness under extreme conditions.

Answer

Slight discoloration of a material over time due to sun exposure.

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