In the passage about the least weasel, which transition is used to introduce an example?

C.

Explanation:

It is the correct answer because On several occasions is a way to introduce an example. The author is telling the reader an example while using a transition word.  Other examples that you could use to introduce an example would be:

another key factor

especially

for instance

for example

in this case

including

such as

to illustrate  

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