The correct option is A Moon
As seen from the Earth, a solar eclipse is a type of eclipse
that occurs when the Moon passes between the Sun and Earth, and the Moon fully
or partially blocks the Sun. This can happen only at new moon when the Sun and
the Moon are in conjunction as seen from Earth in an alignment. In a total
eclipse, the disk of the Sun is fully obscured by the Moon. In partial and
annular eclipses, only part of the Sun is obscured.