Which of These Substances Must Be Primordial

question 9

Multiple Choice

Which of these substances must be primordial?

• A) Helium
• B) Lithium
• C) Deuterium
• D) Beryllium
• E) Tritium

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Definitions:

Stapedectomy

A surgical procedure to remove part or all of the stapes bone in the middle ear, usually to treat hearing loss caused by otosclerosis.

Stapes

The smallest bone in the human body, located in the middle ear, playing a key role in the transmission of sound vibrations.

Prosthesis

An artificial device used to replace a missing body part, such as a limb, tooth, eye, or heart valve.

Hearing Loss

A partial or total inability to hear sounds in one or both ears.