To accurately determine how the lines contribute to an important idea in the poem, it would be helpful to have more context or specific lines from the poem you're referring to. However, based on the options provided, the best choice would depend on the tone, theme, and focus of the poem.
If the speaker is expressing curiosity or inquisitiveness about the tree and is focused on learning or understanding, option 1 or option 4 might be the best fit. If the lines highlight a fascination or appreciation for the tree's characteristics, option 2 or option 3 could be more appropriate.
Please provide additional context or lines for a more precise analysis!