Answer:
a. Disk, 28 thousand light-years from
Step-by-step explanation:
Since, a galactic disc is a component of disc galaxies, for instance spiral galaxies and lenticular galaxies. It consists of a stellar component and a gaseous component.
Also, the Sun lies within the galactic disk or in other words it is thought to be located in the galactic disk,
The Sun is located about 26,000 light-years away from the centre of the galaxy.
∵ From the given options 28,000 is nearest to 26,000
Hence, the sun is about 28 thousand light-years from the centre of the galaxy.
i.e. OPTION 'a' would be correct.