Answer:
A. Forces that act perpendicular to the surface and pull an object apart exert a tensile stress on the object.
Step-by-step explanation:
Tensile stress is referred as a deforming force, in which force acts perpendicular to the surface and pull an object apart, attempting to elongate it.
The tensile stress is a type of normal stress, in which a perpendicular force creates the stress to an object’s surface.
Hence, the correct option is "A."