How is a flexural strength specimen consolidated effectively during the test?

The correct method for consolidating a flexural strength specimen effectively during the test is through rodding and vibration. This process ensures the even distribution of the mix, minimizes air pockets, and maximizes the density of the specimen, which is crucial for achieving accurate flexural strength results.

Rodding involves inserting a rod into the mixture and moving it up and down to break up any air bubbles, while vibration further aids in settling the material and ensuring that it fills all spaces within the mold uniformly. This combined technique helps in achieving the necessary compaction and structural integrity of the specimen, directly influencing the test results for flexural strength.

The other options, while they might have applications in different contexts or for other types of specimens, do not effectively achieve the same level of consolidation as the rodding and vibration method in the specific context of flexural strength testing.