Assignment 1 1. Before testing starts, a program is known to contain 1000 bugs. During testing of the program, four testing techniques are used in succession. Each testing technique is effective in detecting 60% of the bugs present at the time of starting that testing. Further, there is a 50% chance that a bug fix gives rise to a new bug. Approximately how many bugs would remain after application of the four bug detection techniques and correction of the detected bugs? a) 150 b) 200 c) 250 d) 300 Approach: Because of the first testing technique, number of bugs that remain is (1 – 0.6)*1000(bugs undetected) + 0.5*0.6*1000(bug triggered because of the bug fixing technique) i.e. 1000*(0.4 + 0.3) = 0.7 * 1000. So, after four similar testing techniques, the number of bugs that remain is approximately (0.7*0.7*0.7*0.7)*1000 ~ 250 bugs. 2. Which one of the following statements is true about program verification? a) Checks that we are building the right system b) Checks that we are building the system right c) Performed by an independent test team d) Ensures that the developed product is what the user really wants 3. During which phase of the V model of software development are the integration test cases designed? a) Requirements specification b) High-level design c) Detailed design d) Coding 4. Unit testing of a software module does NOT require testing which one of the following? a) Whether coding standards have been followed. b) Whether the functions of the module are working as per design. c) Whether all arithmetic statements of the module are working properly. d) Whether all control statements are working properly. 5. Which one of the following techniques is not a software verification technique? a) Review b) Simulation c) Unit testing d) Beta testing 6. Unit testing is carried out during which one of the following phases of the waterfall model? a) Implementation phase b) Testing phase c) Maintenance phase d) Design phase 7. Which one of the following is NOT a black-box testing technique? a) Decision table testing b) Combinatorial testing c) Mutation testing d) All pair testing 8. When in the waterfall model of software development, is code review carried out? a) After coding is complete and before the code is compiled. b) After coding is complete and after the code is compiled. c) After unit testing is over d) After system testing is over 9. Which one of the following correctly characterizes the negative test cases? a) Invalid test cases b) Test cases not containing permissible input values c) Failed test cases d) Test cases that cannot cause any failures 10. Which one of the following statements is not an objective of software verification? a) Ensuring that product development steps are carried out correctly. b) Ensuring that the correct product has been developed. c) Achieving phase containment of errors. d) Ensuring that the outputs produced at a stage conform to the outputs of the previous phase. .