I agree that E feels weak. This is a must be true (albeit a "most strongly supported" type, which tends to be a tiny bit looser), so we need to prove the statement based on the stimulus. All we are told is that firms are developing a new test, and that the firms argue that these new tests will reduce animal testing.
From this, we probably can conclude that the managers of the firms think it is better not to test on animals if they can avoid it. Since they are developing an alternative to reduce animal testing, their behavior would make absoutely no sense if they didnt belive this.
