Which of the following is true about using field jesses?

Field jesses are an essential piece of equipment in falconry that serve multiple purposes, making the statement that they both prevent entanglement and escaping correct.

Firstly, they are designed to keep the bird secure while allowing a degree of freedom for mobility. The jesses can prevent a bird from escaping when startled, as they ensure that the bird is tethered to the falconer or a perch, reducing the chance that it will fly off when frightened. This is particularly important in training scenarios, where a falconer wants to emphasize control and safety both for the bird and the handler.

Secondly, field jesses can help prevent entanglement, as they allow for a manageable connection to the falconer while minimizing the risk of the bird getting caught in vegetation or other obstacles. This is crucial while hunting or exercising in the field, where the environment can pose various hazards.

Thus, the utility of field jesses encompasses both aspects of preventing entanglement and ensuring the bird does not escape, which results in the answer being correct.