What are PHP variables preceded by?

Answer: Option C

Solution:

This question is about the special symbol that is used in front of a variable in the PHP programming language. Variables are like containers that store information, and PHP uses a specific character to identify them.

Here's how to understand the options:
* Option A: _ This symbol is often used in PHP to represent private members within a class. It's not used to identify variables.
* Option B: @ This symbol is used for error suppression. It tells PHP to ignore any errors that might occur during the execution of the code. It doesn't define a variable.
* Option C: $< / s t r o n g > T hi s i s t h ecor r ec t an s w er! I n < s t r o n g > P H P < / s t r o n g >, v a r iab l es a l w a y s b e g in w i t ha d o l l a r s i g n ($ ). This makes it easy for PHP to recognize them.
* Option D: & This symbol is used for passing variables by reference. It tells PHP to use the actual variable, not a copy of it, which can be important for certain operations.

So, the answer is Option C: $
Let's illustrate with a simple example:
```php $name = "Alice"; echo $name; // This will output "Alice" ```
In this code, ` $nam e ‘ i s a < s t r o n g > v a r iab l e < / s t r o n g > t ha t h o l d s t h e v a l u e " A l i ce ". T h e d o l l a r s i g n ($ ) is what makes it a variable.