A Web page can contain text, graphics, audio, and video, and has built-in connections, or links, to other Web documents.

Which of the following is not allowed?

a. Objects of abstract classes. b. Multiple pure virtual functions in a single abstract class. c. References to abstract classes. d. Arrays of pointers to abstract classes.

sum(n) =1+2+3+...+n, where n>1 is an example of a(n) ____ algorithm.

A. recursive B. iterative C. complex D. infinite