Final answer:
The square root of 21 (\(\sqrt{21}\)) is greater than the square root of 11 (\(\sqrt{11}\)) because square roots increase as their original numbers increase, and 21 is greater than 11.
Step-by-step explanation:
The question asks us to compare the square root of 11 (\(\sqrt{11}\)) and the square root of 21 (\(\sqrt{21}\)). To determine which is greater, we should note that as numbers increase, their square roots also increase. Since 11 and 21 are both positive numbers and 21 is greater than 11, it follows that \(\sqrt{21}\) is greater than \(\sqrt{11}\). Therefore, the correct answer is: b) \(\sqrt{21}\) is greater than \(\sqrt{11}\).