Step 1: Understand the correct usage of "lay" and "lie."
The verb "to lay" is a transitive verb, meaning it requires a direct object. The past tense is "laid" and the past participle is "laid." The verb "to lie" is intransitive, meaning it does not take a direct object. Its past tense is "lay" and the past participle is "lain."
Step 2: Analyze the options.
- (a) "She lays on the bed every night" uses the incorrect form of "lay," as it should be "lies" in this context.
- (b) "She is laying down for a nap" uses the wrong form of "lay." It should be "lying," as "laying" is the present continuous form of the transitive verb "to lay."
- (c) "She has lain the keys on the counter" is also incorrect, as it incorrectly uses the past participle "lain" instead of "laid."
- (d) "She laid the book on the table" correctly uses the past tense of the verb "to lay" with a direct object (the book).
Step 3: Conclusion.
Thus, the correct answer is (d).