Pick out the correct syntax of the header file that can be used with C++.

Which header file is used to include the vector container in C++ STL?

A. <vector>

B. <array>

C. <list>

D. <map>

What does STL stand for in C++?

A. Simple Template Library

B. Standard Template Library

C. System Template Library

D. Structured Template Library

What is the purpose of the 'std::sort' function in C++ STL?

A. To sort elements of a container

B. To search for an element in a container

C. To insert elements into a container

D. To remove elements from a container

Which container in C++ STL does not allow duplicate elements?

A. vector

B. list

C. set

D. map