Which of the following statements correctly emphasize the viewpoint of a developer and a tester with respect to the testing psychology?
I. If a developer implements a fundamental design error (e.g. conceptual misunderstanding), it is HIGHLY probable that he/she will not find is using own tests.
II. The tester can observe the object to be tested without prejudices. It is not his/her own product and the assumptions and misunderstandings of the developer are not, in general, the same as those of the tester.
III. An independent tester must acquire knowledge about the object to be tested in order to create test cases; the developer has good knowledge of the object to be tested and this saves time: hence, it is advisable to assign the test activities to the developer IV. The weakness of the tests done by the developer is that developers tend to be optimistic about their own software. The risk is that reasonable test cases are forgotten because the developer is more interested in development than testing.