The theory is widely regarded as ______ due to extensive testing.

• A. Shaky
• B. Robust
• C. Tentative
• D. Speculative

Answer: (B)

When a theory has been examined through a wide range of tests, it’s described as robust. Robust means strong and reliable, backed by substantial evidence from many experiments and observations. The extensive testing shows the theory’s predictions hold up under different conditions and datasets, so it remains credible even as new data comes in. That resilience and breadth of support is what “robust” captures.

The other options would imply more uncertainty or guesswork. Describing it as shaky suggests instability or vulnerability to new information, which extensive testing argues against. Saying it’s tentative would mean it’s still provisional and open to revision, whereas extensive testing tends to solidify confidence. Calling it speculative would imply little evidence, which clashes with having undergone many tests.