Which of the following is true about templates? 1) Template is a feature of C++ that allows us to write one code for different data types. 2) We can write one function that can be used for all data types including user defined types. Like sort(), max(), min(), ..etc. 3) We can write one class or struct that can be used for all data types including user defined types. Like Linked List, Stack, Queue,..etc. 4) Template is an example of compile time polymorphism.