Two agronomists analyzed the same data, testing the same null hypothesis about the proportion of ...

Two agronomists analyzed the same data, testing the same null hypothesis about the proportion of tomato plants suffering from blight. One rejected the hypothesis but the other did not. Assuming neither made a mistake in calculations, which of these possible explanations could account for this apparent discrepancy?
I.   One agronomist wrote a one-tailed alternative hypothesis, but the other used 2 tails.
II.  They wrote identical hypotheses, but the one who rejected the null used a higher α-level.
III. They wrote identical hypotheses, but the one who rejected the null used a lower α-level.

▸ I only

▸ I or III

▸ III only

▸ II only

▸ I or II