Select the one true statement about deformation and cross-slip:
a) Dislocations of any type can cross-slip in any metal with a FCC crystal structure.
b) A perfect dislocation must react to create two partials and a region of stacking fault before cross- slip onto another slip plane is possible.
c) The region of stacking fault between two partial dislocations increases with increasing stacking fault energy.
d) FCC metals with low stacking fault energy often show a higher strain hardening coefficient.