The following tests are conducted for rails: i) falling weight test ii) tensile test iii) hammer test The compulsory tests are A. Only (i) B. (i) and (ii) C. (ii) and (iii) D. (i) and (iii)

The correct answer is B. (i) and (ii).

The falling weight test is a destructive test that is used to determine the impact resistance of rails. The tensile test is a non-destructive test that is used to determine the tensile strength of rails. The hammer test is a non-destructive test that is used to determine the fatigue strength of rails.

The falling weight test is the most important test for rails because it determines the impact resistance of rails. The tensile test is also important because it determines the tensile strength of rails. The hammer test is less important because it determines the fatigue strength of rails, which is not as important as the impact resistance and tensile strength of rails.

Therefore, the compulsory tests for rails are the falling weight test and the tensile test.