Use De Morgan's law to select the statement that is equivalent to:

"It is not true that the employee received a large bonus and has a big office."

a. The employee received a big bonus or has a big office.

b. The employee did not receive a big bonus and does not have a big office.

c. The employee did not receive a big bonus or does not have a big office.

d. The employee received a big bonus and has a big office.