Obtained a copy of this painting of people in a train for her art collection. what art style did the painter use in this painting?

image of people in a train from honore daumier's painting the third-class carriage

a.
minimalism
b.
realism
c.
cubism
d.
fauvism

The art style that the painter used is called Realism

well seeing i am an artist and i actually did a self portrait; i will describe how i painted it.   i used acrylic on a stretch canvas about 4 feet wide by 6 feet tall. i painted myself smiling in a soft pink long dress, white tile floor sitting on a white couch with a table behind and a vase of gorgeous flowers.   i also had a round white hat with a soft pink ribbon through it laying on the floor and on the table behind me was a lit candle. i kept it simple but soft and romantic.