Which of the following metric prefixes represents the greatest value?

The prefix that represents the greatest value is associated with different orders of magnitude in the metric system. In this case, "Giga" signifies a factor of one billion (10^9).

To put this in perspective, "Kilo" represents a factor of one thousand (10^3), which is significantly lower than Giga. "Mega," which represents a factor of one million (10^6), is also less than Giga. Lastly, "Terra," which denotes a factor of one trillion (10^12), actually represents an even greater value than Giga. Thus, while Giga is a large value, it is not the largest in this context. The largest prefix in the provided choices is "Terra."

Understanding these prefixes is essential in fields such as science and technology, as they help quantify large numbers in a manageable way, which is crucial for calculations, data storage, and communications.