Provide your best answer for the following question. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The question is: A large tree was cut down with a saw. What is the best way to estimate the age of this tree?
count the number of rings in the trunk
The best way to estimate the age of a tree that has been cut down is by counting the growth rings in its trunk.