Rory is trying to identify a tree from one of its leaves using a dichotomous key. A question on the key asks whether the leaf has 3-5 lobes or more than 5 lobes. Rory cannot tell whether the leaf in his hand has 5 or 6 lobes. What should Rory do to continue identifying the tree?

A. Look at other leaves from the same tree and count how many lobes they have.
B. Skip this question, since one question does not make a difference.
C. Start over from the beginning of the dichotomous key.
D. Find a different dichotomous key to use that does not ask this question.

The correct response for Rory is to a. look at other leaves from the same tree to determine the accurate number of lobes, which is integral to using the dichotomous key for tree identification.

Explanation:

If Rory cannot tell whether the leaf in his hand has 5 or 6 lobes, the appropriate step to continue identifying the tree using a dichotomous key would be to look at other leaves from the same tree, and count how many lobes they have. Dichotomous keys require careful observation and often multiple confirmations to ensure the correct path is followed. Since the options in a dichotomous key should be mutually exclusive and jointly exhaustive, having an accurate count of the lobes is critical to follow the correct path in the classification process.

Rory should not skip the question because each question in dichotomous keys is important for accurate identification. Starting over from the beginning won't resolve the uncertainty, and finding a different key might not be practical or relevant, especially if the existing key is specific to the local flora. Therefore, Rory's best option is to examine additional leaves to verify the number of lobes, which would allow for a more confident continuation using the dichotomous key.