**Explanation:**

The word "elan" means enthusiasm, energy, or a lively and confident style or manner. To find the word that is opposite in meaning to "elan," we need to determine a word that represents the opposite qualities or characteristics.

Let's analyze the options given:

a) Brashness: Brashness refers to being bold, loud, or impulsive. It is not the opposite of "elan" as both words can be associated with energy or enthusiasm, although in different ways. Therefore, option a) is not the correct answer.

b) Dignity: Dignity refers to being composed, having self-respect, or behaving in a noble or honorable manner. This is closer to the opposite of "elan" as it represents a more reserved and serious demeanor. However, it does not capture the energetic and lively aspect of "elan." Therefore, option b) is not the correct answer.

c) Composure: Composure refers to being calm, collected, and in control of one's emotions. While it may represent the opposite of being impulsive or brash, it does not capture the energetic and enthusiastic nature of "elan." Therefore, option c) is not the correct answer.

d) Nervousness: Nervousness refers to feeling anxious, worried, or uneasy. This is the closest option to being the opposite of "elan." Nervousness suggests a lack of confidence, energy, and enthusiasm, which are all associated with "elan." Therefore, option d) is the correct answer.

In conclusion, the word opposite in meaning to "elan" is "nervousness" because it represents a lack of confidence, energy, and enthusiasm.