choose the word or group of words that best completes each of the following sentences:
It is I who________to blame for the lapses.
The correct answer is: B
Explanation
When the subject is a pronoun (such as "I," "he," "she," etc.), and it follows the construction "It is [pronoun] who," the verb form should match the pronoun antecedent. Therefore, the correct completion is "It is I who am to blame for the lapses."