Question

summarize it!
drag and drop the words or phrases that accurately complete the paragraph.
scientists have recognized the enormous sizes of and distances between objects in space. they have come up with units of that would communicate the relative sizes and relative distances of these bodies. relative refers to how big the planets are when compared to each other and the sun. relative refers to how far apart the planets are when compared to each other and the sun.
astronomical light year astronomical unit distance universe size measurement galaxy

Explanation:

• "units of measurement" is a common phrase for units used to quantify things.
• "celestial bodies" (though not in the options, but the context implies space - related bodies like planets which are celestial) but among the options, the text is about space objects so we go with the flow.
• "relative size" makes sense for comparing how big planets are.
• "relative distance" makes sense for comparing how far apart planets are.

Answer:

measurement, celestial (but since not in options, we assume the text is about space bodies in general from context), size, distance