Which detail from “The Future of Money” supports the opinion that digital currency is risky? a.“This means there are no official rules used by the government about buying and selling with digital currency.” b. “Just as you can’t spend the same dollar in two places, you can’t spend the same cryptocurrency twice.” c.“You can buy things—goods and services—with bitcoin just as you can buy things with dollars or pesos or euros.”d. “Credit cards can be forged and stolen, but not cryptocurrency.”