Which statement is not correct about internalforce?
Select one:
a. Internal forces describe the stress and strain inside a body,whereas external forces are applied onto the body by itssurroundings.
b. Shear force acts in the axial direction of a beam and tendsto make the beam grow shorter or longer.
c. Bending moment is a reaction produced by the inside of a beamwhen forces are applied to make it bend.
d. There are three types of internal forces in a beam -- shearforce, normal force, and bending moment.
