Answer:
The correct answer is C. Tuberculin skin test.
Step-by-step explanation:
A DTH response, or delayed-type hypersensitivity response, is a type of immune response that is characterized by a slow onset of symptoms. This type of response is typically associated with a type of skin test called the tuberculin skin test, which is used to diagnose tuberculosis. The test involves injecting a small amount of a protein called PPD (purified protein derivative) into the skin, and then observing the skin for any signs of a reaction. If the person being tested has been exposed to tuberculosis, their immune system will recognize the PPD as an invader and mount a DTH response, which can be seen as a small bump or redness at the injection site. This response is an indication that the person has been exposed to tuberculosis.