Which features characterize the Maxmillan sunflower?

The Maxmillan sunflower is distinguished by its rhizomatous growth habit, which allows it to form colonies. This characteristic enables the plant to spread effectively and populate areas. The lanceolate leaves are another defining feature; they are elongated and narrow, which is typical for many sunflower species. This leaf shape helps in maximizing sunlight absorption while minimizing water loss.

The other options describe features typical of other plant species or do not align with the primary characteristics of the Maxmillan sunflower. For instance, while some sunflowers may have broad or ovate leaves, the specific shape and arrangement of the leaves are crucial for identifying the Maxmillan variety. Additionally, while single-stemmed plants can occur in various species, the Maxmillan sunflower's overlapping and extensive rhizomatous spreading is unique to it.