Which of the following is the correct way to declare a hexadecimal value in Java?

Answer: Option A

The correct answer is Option A: 0x1A.

In Java, the correct way to declare a hexadecimal value is by using the prefix 0x followed by the hexadecimal digits.

Here's the breakdown:

Option A: 0x1A - This is the correct way to declare a hexadecimal value in Java. The 0x prefix indicates that the following digits are in hexadecimal format.

Option B: #1A - This is not the correct way to declare a hexadecimal value in Java. Java uses 0x for hexadecimal notation, not #.

Option C: 1A - This is not a valid way to represent a hexadecimal value in Java. It lacks the 0x prefix.

Option D: 0b1A - This is not a valid hexadecimal representation in Java. The 0b prefix is used for binary representation, not hexadecimal.

So, the correct way to declare a hexadecimal value in Java is 0x1A.