The correct answer is (a).
Civil Services Day is celebrated in India on 21 July every year. It is a day to commemorate the foundation of the Indian Administrative Service (IAS) in 1947. The IAS is one of the three All India Services (AIS) of the Government of India, along with the Indian Police Service (IPS) and the Indian Forest Service (IFS).
The IAS is a highly competitive service, and only the best and brightest candidates are selected for it. The IAS officers are responsible for the administration of the country at the state and district levels. They are also responsible for implementing the policies of the central government.
The IAS is a prestigious service, and its officers are held in high esteem by the people of India. They are known for their integrity, honesty, and dedication to duty.
The Civil Services Day is a day to celebrate the achievements of the IAS and its officers. It is also a day to rededicate themselves to the service of the nation.
The other options are incorrect because they are not the dates on which Civil Services Day is celebrated in India.