A $90-$day restriction is imposed under the Federal Reserve Board's

Regulation $T$ requirement for which of the following client transactions?

A The buying and selling of the same stock in different accounts in the same household

The opening and closing of a position in the same stock in a cash account without paying for the stock in full

The buying and selling of the same stock on the same day in a margin account

The opening and closing of a position in the same stock in different accounts on the same day