Suppose you create an uninitialized vector as follows: vector evec; After adding the statement, evec.push_back(21); what will happen?

(A) The following statement will add an element to the start (the back) of evec and will initialize it with the value 21
(B) The following statement will add an element to the center of evec and will reinitialize it with the value 21
(C) The following statement will delete an element to the end (the back) of evec and will reinitialize it with the value 21
(D) The following statement will add an element to the end (the back) of evec and Qinitialize it with the value 21