[A] : Blood plasma is the slightly alkaline, liv- ing intercellular matrix or ground fluid consti- tuting about 40-45% part of the blood.
[R]: Blood plasma does not have a balanced quantity of salt ions for proper functioning of nervous system, muscles and other tissues

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

To solve the assertion and reason question regarding blood plasma, we need to analyze both statements carefully.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Blood plasma is the slightly alkaline, living intercellular matrix or ground fluid constituting about 40-45% part of the blood."
- Blood plasma is indeed slightly alkaline, with a typical pH of around 7.4. However, the statement that it constitutes "about 40-45% of the blood" is incorrect. Blood plasma actually constitutes about 55% of the total blood volume.

2. **Understanding the Reason**:
- The reason states that "Blood plasma does not have a balanced quantity of salt ions for proper functioning of the nervous system, muscles, and other tissues."
- This statement is also incorrect. Blood plasma contains a balanced quantity of electrolytes (such as sodium, potassium, calcium, etc.) that are essential for the proper functioning of the nervous system, muscles, and other tissues. These electrolytes are present in specific concentrations to maintain osmotic balance and support metabolic activities.

3. **Conclusion**:
- Since both the assertion and the reason are incorrect, we conclude that the correct answer is that both the assertion and the reason are false.

### Final Answer:
Both the assertion and reason are false.