By using black verse, Robert Frost accomplished to break the rules. He is often describes as a metricist.
Robert Lee Frost was an American poet. He used to write about settings from rural life in New England in the early twentieth century in an attemp to examine complex social and philosophical themes.
He was considered one of America's rare "public literary figures, almost an artistic institution;" and he received four Pulitzer Prizes for Poetry.
It is answer 4 because the other three are not related to space and even though there are volcanoes on other planet, that question is not as relevant as the other last two.
In Of Wolves and Men, the author uses the word B. minutely (and also delicately) to describe the way in which the wolf inspects the crevice between the rocks.