Question

what do we call stars with high surface temperature and high luminosity?
red giants
white dwarfs
main sequence
red supergiants
blue giants

Explanation:

Red - giants have low surface temperature. White - dwarfs are small and not highly luminous compared to giants. Main - sequence stars have a range of temperatures and luminosities. Red super - giants are cool despite high luminosity. Blue giants are hot and highly luminous.

Answer:

blue giants