The correct answer is option 'b'. The verb is the activity that the subject or object is doing. If you get a doubt regarding the identification of the verb, then make a question out of the statement, ask 

Linking Verb in the Sentence: The cake smells delicious

Explanation:

The given sentence "The cake smells delicious" contains a linking verb, which connects the subject "the cake" to the subject complement "delicious." The linking verb in this sentence is "smells." Here's a detailed explanation of the components of the sentence:

Subject:
The subject of the sentence is "the cake." The subject is the noun or pronoun that the sentence is about. In this case, it refers to a specific cake.

Linking Verb:
The linking verb is the action verb that connects the subject to the subject complement. It does not show any action but rather describes or identifies the subject. In this sentence, the linking verb is "smells," which describes the cake's quality of being delicious.

Subject Complement:
The subject complement is the adjective, noun, or pronoun that follows the linking verb and describes or renames the subject. In this sentence, the subject complement is "delicious," which describes the cake.

Explanation of Incorrect Options:

a) Cake: "Cake" is the subject of the sentence, not the linking verb.

c) Delicious: "Delicious" is the subject complement that describes the cake, not the linking verb.

d) The: "The" is an article that precedes the noun "cake" and does not function as a linking verb.

Conclusion:

The linking verb in the sentence "The cake smells delicious" is "smells." It connects the subject "the cake" to the subject complement "delicious," describing the cake's quality.