What is the meaning of base address of the array?

If a variable is used most frequently then it should be declared using register storage specifier, then possibly the compiler gives CPU register for its storage to speed up the look up of the variable.

A pointer initially holding valid address, but later the held address is released or freed. Then such a pointer is called as dangling pointer.

It is used to alias the existing type. Also used to simplify the complex declaration of the type.

The expression appearing on right side of the assignment operator is called as rvalue. Rvalue is assigned to lvalue, which appears on left side of the assignment operator. The lvalue should designate to a variable not a constant.

The parameters sent to the function at calling end are called as actual parameters while at the receiving of the function definition called as formal parameters.

Yes, it can be but cannot be executed, as the execution requires main() function definition.

When we do not know what type of the memory address the pointer variable is going to hold, then we declare a void pointer for such.

A structure containing an element of another structure as its member is referred so.