Which of the following scenarios reflects the isolation property?

At a shoe store, Pete is buying sneakers.

The checkout clerk begins a transaction for completing the sale.

At the same time, Libby looks up the sneakers on the store's website, in the same size, and it shows they are in stock.

Pete's checkout transaction is completed.

Libby tries to buy the sneakers, but a message appears that the shoes are no longer available.

At a shoe store, Pete is buying sneakers.

The checkout clerk processes Pete's payment and completes the sale.

The store's database server crashes later that day.

Pete calls the store with a question about the shoes, and the clerk is able to look up Pete's purchase in the database.

At a shoe store, Pete is buying sneakers.

The checkout clerk begins a transaction for completing the sale.

There is a power outage at the mall while Pete's credit card is being processed.

When the power is restored, the clerk must start Pete's transaction over from the beginning.