"Tenacious" refers to someone who is persistent and does not give up easily. Option B matches this meaning.
"Ardent" refers to someone who is passionate and enthusiastic, especially about a cause. Therefore, "enthusiastic" is the correct meaning.
"Innovative" means something new and creative. In the context, it refers to a new approach to solving issues, making "creative and new" the correct choice.
"Meticulous" describes someone who pays close attention to detail, meaning thorough and careful. Options A, B, and D are not consistent with the meaning.
"Eloquent" refers to someone who speaks in a clear, expressive, and persuasive manner. Therefore, "expressive and well-spoken" is the most accurate definition.