The correct answer is: A. asterisk
The indirection operator is the asterisk (*). It is used to access the value of a variable or an array element. For example, if x is a variable, then *x is the value of x. If arr is an array, then *arr[i] is the value of the element at index i in arr.
The ampersand (&) is the address-of operator. It is used to get the address of a variable or an array element. For example, if x is a variable, then &x is the address of x. If arr is an array, then &arr[i] is the address of the element at index i in arr.
The dollar sign ($) is the string-concatenation operator. It is used to concatenate two strings. For example, "hello" + "world" is the string “helloworld”.
The plus sign (+) is the addition operator. It is used to add two numbers. For example, 1 + 2 is the number 3.
In conclusion, the indirection operator is the asterisk (*). It is used to access the value of a variable or an array element.