Which of the following sentences has a linking verb?
A. She is fine.
B. She tasted the pizza.
C. She stays at the hotel.
D. She went to the market.

Hint: A linking verb connects the subject with a word that gives information about the subject, such as a condition or relationship.

Complete answer:
Linking verbs do not show any action, they simply link the subject with the rest of the sentence. For example, in the sentence "They are a problem," the word "are" is the linking verb that connects "they" and "problem" to show the relationship between the two words.
Option A) She if fine – is the correct answer because ‘she is fine’ is a linking verb. The subject 'she' is linked with her state of being 'fine' by the linking verb 'is'. Thus, this is the correct answer.
Option B) She tasted the pizza – is an incorrect answer because 'She tasted the pizza' does not have a linking verb. 'Tasted' is a normal verb as it doesn't define the subject's complement, adjective or state of being. Thus, this is an incorrect answer.
Option C) She stays at the hotel – is an incorrect answer because She stays at the hotel' doesn't have a linking verb. 'Stays' is a normal verb, it does not link the subject 'she' with any complement or adjective here. Thus, this is an incorrect answer.
Option D) She went to the market – is an incorrect answer 'She went to the market' doesn't have a linking verb. 'Went' is a normal verb that simply expresses the action of the subject. Thus, this is an incorrect answer.

She is fine (option A) has a linking verb.

Note:
Linking verbs are forms of the verb i.e. am, is, was, were and etc. and linking verbs connects the subject with an adjective or a noun that describes it. They do not describe any direct action or control by the subject. Linking verbs are little different from helping verbs and helping verbs are auxiliary verbs that are used together with the main verb of the sentence to express the action.