The last point on the stress-strain curve that occurs after the ultimate stress point is the

The correct answer is option 4) i.e. Fracture point.

CONCEPT:

Stress-strain curve: 

• ​It is the curve representing the relationship between stress and strain.
• The curve is obtained by applying different amounts of loads(stress) on a test material and recording the respective deformation(strain) in the load.
• The curve is useful in estimating the different properties of a material such as Elastic modulus, yield strength, ultimate tensile strength etc.

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EXPLANATION:

• The endpoint of the stress-strain curve is the fracture point that is the point at which any further stress will cause the breaking or fracture of the material.

Additional Information

• Upper and lower yield point: The stress at which the material starts to yield or starts transiting from elastic to plastic deformation is called the upper yield limit or upper yield stress point. As deformation continues, the stress falls abruptly to a value called the lower yield point.
• At the end of the proportionality limit, the stress-strain proportionality reaches its maximum extent and the point after that is known as the elastic point.