The correct answer is: A. ancestors of modern man.
Ramapithecus and Cro-Magnon man are both considered to be ancestors of modern man. Ramapithecus was an early hominid that lived in Africa between 14 and 8 million years ago. It is thought to be the ancestor of the genus Homo, which includes modern humans. Cro-Magnon man was a type of early human that lived in Europe between 40,000 and 10,000 years ago. They are considered to be the direct ancestors of modern humans.
Option B is incorrect because Ramapithecus and Cro-Magnon man are not considered to be ancestors of monkeys. Monkeys are a different group of primates that diverged from humans and apes millions of years ago.
Option C is incorrect because Ramapithecus and Cro-Magnon man are not considered to be ancestors of lions. Lions are a type of cat that diverged from other cats millions of years ago.
Option D is the correct answer because Ramapithecus and Cro-Magnon man are both considered to be ancestors of modern man.