a) Hardtop processing capabilities are huge and its real advantage lies in the ability to process terabytes & petabytes of data
b) Hadoop uses a programming model called “MapReduce”, all the programs should conform to this model in order to work on the Hadoop platform
c) The programming model, MapReduce, used by Hadoop is difficult to write and test
d) All of the mentioned

Answer: c
Explanation: The programming model, MapReduce, used by Hadoop is simple to write and test.