@Daviday51101994 On day 1 the doubling option yields $1 (2^0), scaling to 2^(n-1) dollars on day n.
The amount first exceeds $2 billion on day 32, when it reaches exactly 2^31 = $2,147,483,648.
By day 33 it doubles again to $4,294,967,296
. So I'll choose 1 dollar that doubles daily.