Question: Which sentence is correctly structured?

Options:

1. Running late, the bus was missed by John.
2. The teacher, who was late, arrived at class.
3. The cake, which was delicious, was eaten by us.
4. She quickly ran to the store, and bought some milk.

Correct Answer: The cake, which was delicious, was eaten by us.

Solution:

The third option correctly uses commas to set off the non-restrictive clause \'which was delicious\'.