Answer: I cant give you an exact answer, but your options are gonna be B or C.
Explanation: A computer programmer actually doesn't work with a marketing company at all, most of them work from home as it is. And a Tech Support Specialist may work with a marketing firm, but it would be strictly IT stuffs.
An internal node is a node which carries at least one child or in other words, an internal node is not a leaf node.
Document.write()
I'm not sure that this is a method, but I think this is right.