Assertion : A bacterial cell with restriction enzymes will be easily infected and lysed by bacteriophages.
Reason : Restriction enzymes catalyse synthesis of protective coat around bacterial cell that prevents bacteriophage attack.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that a bacterial cell with restriction enzymes will be easily infected and lysed by bacteriophages. This implies that the presence of restriction enzymes does not provide any protection against bacteriophages.

2. **Analyzing the Role of Restriction Enzymes**: Restriction enzymes are proteins found in bacteria that serve as a defense mechanism against foreign DNA, including that from bacteriophages. They work by recognizing and cleaving specific sequences of foreign DNA, thereby preventing the bacteriophage from successfully infecting the bacterial cell.

3. **Evaluating the Assertion's Validity**: Since restriction enzymes cleave the DNA of bacteriophages, the assertion that a bacterial cell with these enzymes will be easily infected is incorrect. Therefore, the assertion is false.

4. **Understanding the Reason**: The reason provided states that restriction enzymes catalyze the synthesis of a protective coat around the bacterial cell that prevents bacteriophage attack. This suggests that restriction enzymes create a physical barrier to protect the bacteria.

5. **Analyzing the Reason's Validity**: This statement is also incorrect because restriction enzymes do not synthesize a protective coat. Instead, they function by cleaving foreign DNA. Hence, the reason is false.

6. **Conclusion**: Both the assertion and the reason are false. Therefore, the correct answer is that both the assertion and the reason are false.

**Final Answer**: Option D - Both assertion and reason are false.

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