Explanation:

- The sentence in question is: "He had a frugal lunch."

- The word "frugal" means economical, saving, or not spending much.

- We need to find the opposite of "frugal."

Let's examine the options:

1. Sparing: This means using or spending very little; similar to frugal.

2. Extravagant: This means spending much more than is necessary or wise; wasteful. This is the opposite of frugal.

3. Meagre: This means lacking in quantity or quality; similar to frugal.

4. Delicious: This describes the taste of the lunch, not the quantity or cost.

- The opposite of "frugal" is indeed "extravagant."

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