**Core Concept**
The question is testing the understanding of the relationship between a specific infection site and the resulting distant complications. In this case, the infection of the great toe can lead to the formation of multiple sinuses, which are abnormal connections between the skin and deeper tissues or organs. This phenomenon is a classic example of a hematogenous spread of infection.

**Why the Correct Answer is Right**
The correct answer is related to the bacteremia caused by Staphylococcus aureus, which is a common cause of skin and soft tissue infections, including those of the great toe. When Staphylococcus aureus enters the bloodstream, it can cause a condition known as septic emboli, where the bacteria are deposited in various organs and tissues, leading to the formation of abscesses and sinuses. In this case, the multiple sinuses are a result of the hematogenous spread of Staphylococcus aureus from the infected great toe.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because E. coli is a common cause of urinary tract infections and is less likely to cause sinuses from an infected great toe.
* **Option B:** This option is incorrect because Pseudomonas aeruginosa is a common cause of respiratory infections and is not typically associated with the formation of sinuses from a skin infection.
* **Option D:** This option is incorrect because Klebsiella pneumoniae is a common cause of pneumonia and is not typically associated with the formation of sinuses from a skin infection.

**Clinical Pearl / High-Yield Fact**
When a patient presents with multiple sinuses, it is essential to consider the possibility of a distant infection site, such as the great toe, as the source of the complication. This is a classic example of a hematogenous spread of infection, and identifying the underlying cause is crucial for effective treatment.

**Correct Answer:** C. Staphylococcus aureus.