Answer:
The answer option that best describes when a lunar eclipse will occur is "when the Moon passes between the Earth and the Sun."
Step-by-step explanation:
During a lunar eclipse, the Earth is positioned between the Sun and the Moon. As the Moon moves into the Earth's shadow, it begins to darken and eventually turns a reddish-brown color. This occurs because the Earth's atmosphere bends some of the Sun's light, causing it to be refracted or redirected toward the Moon. This refracted light is mostly red, which is why the Moon takes on a reddish hue during a lunar eclipse. Therefore, the option "when the Moon passes between the Earth and the Sun" best describes when a lunar eclipse will occur.