Using the HR diagram below, how would a star that is less luminous than the Sun, with a temperature lower than 3000K be classified?

Using the HR diagram below, how would a star that is less luminous than the Sun, with a temperature lower than 3000K be classified?

A supergiant in spectral class K.

A white dwarf in spectral class B.

A main-sequence star in spectral class M.

A main-sequence star in spectral class K.

A main-sequence star in spectral class M.