Ared dwarf is a. the remains of a supernova. b. a hot pulsar. c. a white dwarf that has cooled. d. a small main sequence star. e. a prostar

Option D, a small main sequence star

Explanation:

A red dwarf is just like a small main sequence star as it is formed in the same way as a main sequence star. They are of very small size equivalent to 8 to 50 % of the mass of the sun. They get reduced in size due to  their lower burning temperature as they burn using their hydrogen supply less rapidly unlike other main sequence stars which burns their hydrogen supply rapidly

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.

yes it is weird but true