Which of these stocks is considered the "riskiest" investment as measured by their respective beta's?

Facebook $($META$)-$ Beta: $1\mathrm{.}39$

Target $($TGT$)-$ Beta: $1\mathrm{.}01$

Walmart $($WMT$)-$ Beta: $0\mathrm{.}53$

Apple $($AAPL$)-$ Beta: $1\mathrm{.}21$