Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: It should not have mattered because it did not matter to me , but it was one of those reactions . Those urges built in before humans took that step forward from primates . Can I blame this on evolution ? Or you ?

Question: Why does the narrator think they reacted the way they did ?
It was a natural urge .
The reason for the narrator's reaction is not clear from the text.