Identify the correct voice transformation. **They should have completed the assignment by now.**

Options:

• A: The assignment should completed by now.
• B: The assignment has been completed by now.
• C: The assignment must have completed by now.
• D: The assignment should have been completed by now.

Related Practice Questions:

• Why is copper considered highly pure and extensively used in religious rituals by Hindus today according to the historical context of natural resources?
• Which of the following regions is described by R.S. Sharma as "the most coveted and contested area" fought over by important ruling powers in northern India?
• Paper currency was not used in ancient India. In which century was paper currency finally introduced to India?
• The earliest agricultural settlements and states in ancient northern India were founded along the Himalayan foothills (the "terai" route) during which period?