Which of the following is a property of most metalloids?

• A. They have intermediate electrical conductivity.
• B. They are highly malleable.
• C. They readily form basic oxides.
• D. They are excellent conductors of heat.

Answer: (A)

Verified step by step guidance

1. Understand what metalloids are: Metalloids are elements with properties intermediate between metals and nonmetals.
2. Recall the typical properties of metalloids, such as their electrical conductivity, malleability, oxide formation, and thermal conductivity.
3. Evaluate each option by comparing it to known metalloid characteristics: For example, metalloids usually have electrical conductivity that is between that of metals and nonmetals, meaning they are semiconductors.
4. Recognize that metalloids are generally not highly malleable like metals, nor do they typically form basic oxides (which is more characteristic of metals).
5. Conclude that the property 'They have intermediate electrical conductivity' best describes most metalloids, as this is a defining feature of their behavior.