SECTION 1 TIME— 30 MINUTES 38 QUESTIONS DIRECTIONS

20. The passage presents which of the following as

stars are not highly luminous. Third, no one has

incontrovertible?

detected in the corona the clouds of gaseous matter

I. The low luminosity of old stars

such as hydrogen and carbon monoxide that are

characteristic of the bright parts of a galaxy. At

II. The absence of clouds of gaseous matter

present, therefore, the best explanation— though

from the corona of the Milky Way

still quite tentative— for the darkness of the

III. The predominance of globular clusters and

corona is that the corona is composed mainly of

dwarf galaxies in the corona of the Milky

Way

old burned-out stars.

(A) I only