Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: 
Most modern plants, like the skunk cabbage, produce flowers. However, flowers evolved relatively late in the history of plants. The earliest plants not only lacked flowers. They also lacked leaves, roots, and stems. They probably resembled the alga in Figure below .


Question: The earliest types of what lacked flowers, leaves, roots and stems?
plants
The earliest plants.