If a particular cell is known to be round and incapable of producing its own food, such a cell would not be a plant cell. As such, from the options below:
The correct answer as to which of the organelles the cell must have would be the plasma membrane.
Hence, since it has been established that the cell is not a plant cell, the only organelle left that the cell cannot do without is the plasma membrane.
More on cell organelles can be found here: https://brainly.com/question/23802482