Which sentence correctly uses commas to separate a nonrestrictive modifier?

The man, who owned the floral shop, watered the shop’s hanging plants.
The young child-who is my nephew- is the cutest three-year-old ever!
My friend John, who owns a chocolate Lab puppy, is getting ready to leave for a trip.
The student, who aced the test, was excused from completing the homework assignment.

My friend John, who owns the chocolate Lab puppy, is getting ready to leave for a trip.

Explanation:

"Nonrestrictive modifiers" are words or phrases that follows a noun. It is separated by commas since it presents an information that is not essential to the meaning of the sentence as a whole.

Among the choices above, the choice "My friend John, who owns the chocolate Lab puppy, is getting ready to leave for a trip" uses the commas correctly in order to separate its non restrictive modifier.

The non restrictive modifier in the sentence is "who owns the chocolate Lab puppy." This modifies "My friend John." However, it is not an essential information in order to determine the meaning of the whole sentence since the sentence already mentioned the named John.  

d

explanation: