The accumulation of this substance in the body causes Gout

The correct option is Uric acid.

Step-by-Step Explanation:

1. Understanding Gout: Gout is a painful form of inflammatory arthritis. It typically affects one joint at a time, often the big toe, causing severe pain, swelling, redness, and warmth in the affected joint.

2. The Role of Purines: Purines are natural chemical compounds found in the cells of our bodies and in many of the foods we eat (such as red meat, organ meats, and seafood). When the body breaks down purines, it produces a waste product called uric acid.

3. Formation of Uric Acid Crystals: Normally, uric acid dissolves in the blood, passes through the kidneys, and is eliminated from the body in urine. However, if the body produces too much uric acid or the kidneys excrete too little of it, the levels of uric acid build up in the blood. This condition is known as hyperuricemia.

4. Crystal Deposition: When uric acid concentrations become excessively high, it can form sharp, needle-like urate crystals in and around the joints or surrounding tissues. The body's immune system reacts to these crystals as foreign invaders, triggering an inflammatory response that leads to the intense pain and swelling characteristic of a gout attack.

5. Conclusion: Therefore, the accumulation of uric acid is the direct chemical cause of gout, making it the correct answer.