Answer:
B). Subj- Taking my dog for a walk; FV- is
Step-by-step explanation:
The subject is defined as the 'word or word group(noun or noun phrase) that is dealt with in a sentence.' While the finite verbs are characterized as the verbs that reflect the agreement with the subject and marks the tense/time in the sentence. Thus, 'taking my dog for a walk' is the subject of the given sentence as it being dealt with in this sentence, and 'is' is the finite verb as it shows the agreement with the given subject and reflects the present tense. Hence, option B is the correct answer.