Which of the following bacterium is responsible for causing urinary tract infections?

Options

A. Staphylococcus saprophyticus
B. Streptococcus pyogenes
C. Staphylococcus aureus
D. Streptococcus pneumoniae

Answer

**Step-by-Step Solution:**

1. **Understanding Urinary Tract Infections (UTIs):**
- Urinary tract infections are infections that can occur in any part of the urinary system, including the bladder, urethra, and kidneys.

2. **Identifying Common Bacteria Responsible for UTIs:**
- The most common bacteria that cause UTIs include Escherichia coli (E. coli), Staphylococcus saprophyticus, and others. However, the question specifically asks for one bacterium.

3. **Analyzing the Options Given:**
- The options provided include:
- A) Staphylococcus saprophyticus
- B) Streptococcus pyogenes
- C) Staphylococcus aureus
- D) Streptococcus pneumoniae
- We need to identify which of these is primarily associated with UTIs.

4. **Evaluating Each Option:**
- **Staphylococcus saprophyticus:** Known to be one of the bacteria that can cause UTIs, particularly in young sexually active women.
- **Streptococcus pyogenes:** Primarily known for causing throat infections and skin infections, not UTIs.
- **Staphylococcus aureus:** Generally associated with skin infections and other systemic infections, not specifically UTIs.
- **Streptococcus pneumoniae:** Mainly causes pneumonia and is not associated with UTIs.

5. **Conclusion:**
- Based on the analysis, the bacterium responsible for causing urinary tract infections is **Staphylococcus saprophyticus**.

**Final Answer:** Staphylococcus saprophyticus

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