Hich of the following usually indicates that there is no moreinput to be read by a program?
a)'\n'
b)'\0'
c)end
d)eof

EOF

Explanation:

End of file(EOF) indicates that there is no more input to be read from the program. When we open a file we use fprintf to print all the characters present, this printing continues until we reach the end of the file by checking a condition where we have reached the end of the file.

Then it terminates out of the loopwhen there are no more characters to be printed.

i believe the two important functions that skype uses are nat traversal and user location.good luck        

explanation: