The correct answer is:
A. Jerry looks ill today.
Explanation:
A predicate adjective is used to describe, or modify the subject, and comes right after the linking verb, which is used to connect the subject with the predicate adjective (the word that describes the subject).
- ill: predicate adjective.
Option B cannot be correct because it doesn't contain an adjective, disdainfully is an adverb (it modifies the verb not the subject).
Option C and D are incorrect because they contain prepositional phrases, "at the map", "into the microscope"; they start with a preposition and end with a noun, both phrases describe what the subject is looking instead of modifying the subject.