Question

fff: warping
use the information below to answer the question.
support structure material
support material can be used in a number of ways. while it is often used to support
parts that overhang past the base of the print, support material can also cause a
reverse in tension, preventing warpage in susceptible flat planes.
design support planes
if your part requires a large flat plane to be printed, you may be able to add support to
it by printing another flat surface next to it. this will help support the plane as it is
being printed.
design chamfered edges
chamfers are used to provide a radius around the edge of an object. when designing a
what tends to happen to large, flat, unsupported planes in a
build?
they often warp.
they are often restricted.
they often expand.

Explanation:

The text states that support material can prevent warpage in flat planes. This implies that without support, large, flat planes would warp. The other options (restricted, expand) are not mentioned in the context related to the problem.

Answer:

They often warp.