A carpenter glues a pair of cylindrical wooden logs by bonding their end faces at an angle of θ = 30° as shown in the figure.The glue used at the interface fails ifCriterion 1: the maximum normal stress exceeds 2.5 MPa.Criterion 2: the maximum shear stress exceeds 1.5 MPa.Assume that the interface fails before the logs fail. When a uniform tensile stress of 4 MPa is applied, the interface

• A. fails only because of criterion 1
• B. fails only because of criterion 2
• C. fails because of both criteria 1 and 2
• D. does not fail