Final answer:
The verb 'become' in the sentence acts as a linking verb, connecting the subject with additional information about its status.
Step-by-step explanation:
The question asks to identify the type of verb used in the sentence 'White House pets often become almost as well known as their owners.' The verb in question is 'become,' and in this context, it is acting as a linking verb. A linking verb connects the subject with a word that gives information about the subject, in this case, connecting 'White House pets' with the complement 'almost as well known as their owners,' which describes the pets' status or condition.