Answer:
(C) The HR department has known about the insurance premium increase for six weeks.
(D) She gave me the Lincoln Laser billing records before she left on vacation.
Explanation:
The subject verb agreement in options C and D are correct.
Option C: The use of 'has known' is in the past form, thus the sentence is correct.
Option D: 'gave' is also a past tense, which agrees with the sentence as she had left for the holiday.
Whereas, Options A and B are wrong.
Option A: the board has chosen, meaning 'past tense' thus the use of 'accepts' which is a present tense is wrong.
Option B: the new policy had been started since yesterday, so the verb 'begun' which is the "third form of the verb' is wrong and should be used alongside a helping verb thus making it 'had begun'.
