By volume of water, which lake is the largest in Scotland, holding the greatest quantity of freshwater?

Introduction / Context:
Lakes can be compared using different measures such as surface area, maximum depth and total volume of water they contain. In Scotland, several famous lochs are well known in geography and general knowledge, and many competitive exams ask which one is the largest by a particular criterion. This question focuses specifically on volume of water, not surface area, and asks you to identify which Scottish lake holds the greatest quantity of freshwater.

Given Data / Assumptions:

• The options list four important Scottish lochs: Loch Lomond, Loch Ness, Loch Awe and Loch Maree.
• The key phrase in the question is by volume of water, which is different from largest surface area.
• We assume standard information used in school geography and general knowledge resources.

Concept / Approach:
Loch Ness is world famous not only for legends about a mysterious creature but also for its great depth and volume. While Loch Lomond has the largest surface area of any lake in Scotland, Loch Ness is much deeper and therefore contains a larger total volume of water. The volume depends on both area and depth, and the exceptional depth of Loch Ness makes it the largest by volume. Loch Awe and Loch Maree are also significant but do not surpass Loch Ness in total water content.

Step-by-Step Solution:
Step 1: Distinguish between surface area and volume: surface area is the size of the lake surface, whereas volume is the total quantity of water held.Step 2: Recall that Loch Lomond is known for having the largest surface area among Scottish lakes.Step 3: Remember that Loch Ness is famous for being very deep, with a long narrow shape and great maximum depth.Step 4: Understand that because of this depth, the total volume of water in Loch Ness is greater than in other Scottish lochs.Step 5: Therefore identify Loch Ness as the largest lake in Scotland by volume of water.

Verification / Alternative check:
Geographical facts presented in reference books and educational websites often state that Loch Ness contains more freshwater than all the lakes in England and Wales combined. This statement highlights its enormous volume. In contrast, Loch Lomond is highlighted for surface area rather than depth. When exam keys and geography tables are consulted, Loch Ness consistently appears at the top when ranking Scottish lakes by volume, confirming that it is the correct answer for this question.

Why Other Options Are Wrong:
Loch Lomond: Largest in surface area within Scotland, but shallower compared with Loch Ness, so its total volume is smaller.Loch Awe: Important and scenic, but neither the deepest nor largest by volume when compared with Loch Ness.Loch Maree: Also a major loch, yet it does not match the combined area and depth that make Loch Ness number one in total water content.

Common Pitfalls:
A very common error is to confuse the largest by area with the largest by volume. Many candidates remember that Loch Lomond is largest in one respect and pick it without noticing the wording by volume of water. Another pitfall is to be distracted by the legend of the Loch Ness monster and not take Loch Ness seriously as a geographic fact. Careful reading of what is being asked, together with a clear memory that Loch Ness is the deepest and therefore holds the greatest volume, will help you avoid such mistakes.

Final Answer:
By volume of water, the largest lake in Scotland is Loch Ness.