Step 1: Mission Indradhanush is named after the seven colours of the rainbow and was launched to fully immunise children against seven vaccine-preventable diseases.
Step 2: The seven diseases originally targeted are diphtheria, pertussis, tetanus, childhood tuberculosis, polio, hepatitis B and measles. Japanese encephalitis is not part of this original list of seven, so it is the vaccine not included. Hence option 3 is correct.
Step 3: Why the others are wrong. Tuberculosis (BCG), measles and diphtheria are all on the core seven-disease list of the mission, so they are included and cannot be the answer.