Select the most appropriate ANTONYM of the underlined word in the given sentence.
The performance of the team in the lost match was dismal.

The correct answer is Luminous.

Explanation:

In the given sentence, the word "dismal" means gloomy, depressing, dark, or showing/causing a lack of hope and cheer.

Let us analyze the meaning of the given options:

1. Luminous: Giving off light; bright or shining. This is the exact opposite (antonym) in tone and visual/metaphorical representation of "dismal" (dark/gloomy).

2. Sadden: To cause someone to feel unhappy or sad.

3. Cheap: Low in price or of low quality.

4. Dainty: Delicately small and pretty.

Therefore, the most appropriate antonym for dismal is Luminous.