The correct answer is A. Mughalsarai.
Mughalsarai is a railway junction in Uttar Pradesh, India. It is the largest marshalling yard in India, and also the longest in Asia. The yard is located on the Grand Chord railway line, and is a major hub for both passenger and freight traffic. Mughalsarai is also home to the Mughalsarai Junction railway station, which is one of the busiest railway stations in India.
The other options are incorrect. Mathura is a city in Uttar Pradesh, India. It is a major pilgrimage site for Hindus, and is home to the Krishna Janmabhoomi temple. Itarsi is a city in Madhya Pradesh, India. It is a major railway junction, and is located on the Howrah-Nagpur main line. Guntakal is a city in Andhra Pradesh, India. It is a major railway junction, and is located on the Howrah-Chennai main line.