Step 1: Define the term in the question.
An extreme desire for wealth is also known as greed.
Step 2: Define the options.
Omnivorous: Feeding on both plants and animals.
Avaricious: Having or showing an extreme greed for wealth or material gain.
Gregarious: Fond of company; sociable.
Carnivorous: Feeding on other animals.
Step 3: Match the definition.
The word "Avaricious" is the exact term for having an extreme desire for wealth.