When budgeting projects using Agile methods, which statement BEST describes spike?

a. Short, time-boxed effort to test the concept to reduce risk 

b. Perform as much testing and risk reduction early to gain feedback as soon as possible so needed changes can be made quickly 

c. The process of developing an approximate and best guess of the monetary value of resources needed to complete all project activities 

d. A quantified assessment of the likely amount. It should always include an indication of accuracy