Can I pick between the BSD license and the GPLv2 license?

[Mike4Online]

According to Wikipedia's article on multi-licensing, software can be published under a dual-license whereby BOTH licenses must be adhered to. Your GitHub readme.md file does not clearly indicate whether both licenses always apply, or whether I can pick (e.g. BSD over GPLv2). Please clarify.

Thanks

[Cyan4973]

This is the simpler case :
"When software is multi-licensed, recipients can typically choose the terms under which they want to use or distribute the software"

It's also specified at the top of each file :
https://github.com/facebook/zstd/blob/dev/lib/zstd.h#L8

You may select, at your option, one of the above-listed licenses.