Which of the following have maximum `pH`?

Options

A. Black coffee
B. blood
C. Gastric juice
D. Saliva

Explanation

To determine which of the given options has the maximum pH, we need to analyze the pH values of each option provided. The pH scale ranges from 0 to 14, where lower values indicate acidic solutions, and higher values indicate basic (alkaline) solutions. Here’s how we can solve the question step by step:

### Step-by-Step Solution:

1. **Identify the pH of each option:**
- **Black Coffee:** The pH of black coffee is approximately 5.
- **Blood:** The pH of blood ranges from 7 to 7.4.
- **Gastric Juice:** The pH of gastric juice is between 1.8 to 2, indicating a strong acidic solution.
- **Saliva:** The pH of saliva is around 6.8.

2. **Compare the pH values:**
- Black Coffee: pH = 5
- Blood: pH = 7 to 7.4
- Gastric Juice: pH = 1.8 to 2
- Saliva: pH = 6.8

3. **Determine the maximum pH:**
- Among the values listed, Blood has the highest pH, which is 7.4.

4. **Conclusion:**
- Therefore, the substance with the maximum pH among the given options is **Blood**.

### Final Answer:
The correct answer is **Blood (option B)**.

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