Explanation:

Let’s break this down:

- The underlined word is generosity (meaning: giving plenty, being liberal with portions).

- Option 1: Amplitude – That basically means largeness or abundance. Not the opposite; it's pretty similar.

- Option 2: Richness – That means wealth or abundance. Again, not the opposite.

- Option 3: Dearth – This means scarcity or lack of something. That’s the opposite of generosity.

- Option 4: Abundance – More than enough, a lot of something. Close in meaning to generosity.

So, the right answer is:

Option 3: Dearth

Generosity = plenty; dearth = not enough. Everything else is some form of plenty or richness. You got it.