The answers are A, F and H.

The sentence discusses how philosophers of science try to avoid appearing overly biased or dogmatic. As a result, when they advance a thesis, they immediately qualify or limit it themselves. The final part explains that even when there is a great deal of evidence, disagreement and competing interpretations still continue.

Blank (i):
A. tendentious: Tendentious means biased or pushing a particular agenda. This fits perfectly because philosophers of science want to avoid appearing overly ideological or one-sided.
B. naive: Naive means inexperienced or overly innocent. The sentence is not concerned with lack of sophistication, but with appearing biased.
C. credulous: Credulous means too willing to believe things. This does not fit the context of carefully defending and qualifying arguments.

Blank (ii):
D. abandon: Abandon means completely give up. The sentence suggests philosophers qualify or limit their thesis, not discard it entirely.
E. preempt: Preempt means act before someone else does. While philosophers may anticipate criticism, the sentence specifically suggests limiting or qualifying the thesis itself, not merely acting first.
F. circumscribe: Circumscribe means limit or restrict. This fits perfectly because philosophers instinctively qualify and narrow their own claims to avoid appearing dogmatic.

Blank (iii):
G. ambiguous: Ambiguous means unclear. However, the sentence says that rival interpretations proliferate even when evidence is plentiful, so ambiguity is not the point.
H. abundant: Abundant means plentiful. This fits perfectly because the sentence emphasizes that disagreement persists despite a large amount of evidence.
I. corroborated: Corroborated means confirmed or supported. While evidence can corroborate a theory, the structure “experimental evidence is corroborated” is awkward and does not fit naturally here.