$.$ A Bitcoin private key is a very long string of

either alphanumeric code or a string of either

zeros or ones, called bits. Bitcoin private keys

are how many bits:

A$.109$ bits

B$.256$ bits

C$.314$ bits

D$.499$ bits

$36.$ The oldest stablecoin is $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.$

A$.$ USD Coin $($USDC