California Registered Dental Assistant (RDA) Written Practice Exam

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Master the California Registered Dental Assistant (RDA) Written Exam with our comprehensive practice quiz. Tailored to mimic real exam conditions, it's your key to unlocking success and advancing your dental assisting career.

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What does 'hydro-' mean?

Air
Earth
Water
Fire

The correct answer is: Water

'Hydro-' is a prefix that is derived from the Greek word 'hydor', meaning "water." Therefore, 'hydro-' refers to anything related to water such as hydroelectricity, hydrophobic, or hydrotherapy. Option A, air, and option D, fire, have their own respective prefixes 'aero-' and 'pyro-' and are not related to 'hydro-'. Option B, earth, may potentially be confused with 'hydro-' since water is found on earth, but the prefix for earth is actually 'geo-'. So, option C is the only one that accurately defines the meaning of 'hydro-'.