3. which of the following is not a safe serving technique?
a. use tongs to serve rolls to customers
b. change the linens in the bread basket each time it is re-used
c. hold flatware by the stem
d. re-serve uneaten bread

D. Re-serve uneaten bread

Explanation:

Re-serve uneaten bread   is NOT a safe serving technique because once an aliment has left the kitchen or the prep stations, you don't know what happened to them.

Although unlikely, the customers would have placed something in the bread.  Bigger risk is that they just handled them with uncleaned hands spreading their germs all over.  So, that bread cannot be considered safe to serve to a new client.