Light year is the unit of?

Light year is the unit of:

                          Answer:a
                     Hints & solution:
 Light year is the unit of length.                                        1 light year=9.46×10^15m.                                  1 Astronomical unit=1.46×10^11m.
                1A°=10^-10m.
  1nm=10^-9m.
1micro meter=10^-6m.
1 X-ray unit=10^-13m.
1 Fermi=10^-15m.

• The smallest unit of distance in nuclear physics is fermi.