Which operator is used to access the value stored at a pointer address in C?

Answer: Option C

In C, the * operator is used to access the value stored at a pointer address. It is called the "dereference" operator and is used to obtain the value that the pointer is pointing to.

Option A (&) is the address-of operator, used to obtain the memory address of a variable.
Option B (->) is used to access members of a structure or union through a pointer to that structure or union.
Option D (.) is used to access members of a structure or union directly, not through a pointer.