In the case of plane strain, the relationship between the fracture toughness and crack extension force is given as _______ (where K is the fracture toughness, δ is the crack extension force, ν is the poison’s ratio, and E is the young’s modulus).

In the case of plane strain, the relationship between the fracture tou

1.	In the case of plane strain, the relationship between the fracture toughness and crack extension force is given as _______ (where K is the fracture toughness, δ is the crack extension force, ν is the poison’s ratio, and E is the young’s modulus).
A.	K=δE
B.	K2=δE/(1-ν2)
C.	K=(δE)/ν
D.	K=δ/E
Answer» C.