The question asks which line of longitude passes through central India. There seems to be a confusion in the question as the options are lines of latitude. Assuming the question meant to ask about the important line of latitude that passes through central India.
Lines of latitude are imaginary horizontal lines, while lines of longitude are imaginary vertical lines.
Tropic of Cancer: This is a line of latitude located at approximately 23.5° North of the Equator. It passes through the middle of India, dividing the country into roughly two equal parts. It passes through eight Indian states.
Tropic of Capricorn: This is a line of latitude at 23.5° South of the Equator. It does not pass through India.
Equator: This is the line of latitude at 0°. It does not pass through India.
Based on the options, the Tropic of Cancer is the correct line of latitude that passes through central India.
The Standard Meridian of India, which is a line of longitude (82.5° East), also passes through the central part of the country but is not an option.