Correct option is C
From the given statement following Venn diagram will be drawn-

Conclusions:
I. Some sunflowers are carnations. ( True, as per the diagram.)
II. All carnations are sunflowers. ( False, as per the diagram.)
III. All petunias are carnations. ( False, as per the diagram.)
IV. No sunflower is a carnation. ( False, as per the diagram.)
Correct answer is (c).