This question tested your ability to spot an often easy to overlook error, a missing "i" verb. The reason this is easy to miss is purely visual, in the middle of a visually complex word like "deficient" it is almost natural to overlook a missing letter. It is important, when proofreading or having your spelling tested, to give words an extra look, to make sure that your eye hasn't naturally filled in a missing letter.

The rest of these adjectives are all spelled correctly.