Which tick stage lacks eyes?

The correct answer indicates that all stages of the Blacklegged "Deer" Tick lack eyes. Ticks are arachnids, and unlike many other arthropods, they do not possess compound eyes. Instead, they have simple eyes, or ocelli, which are rudimentary and not always present in all life stages.

In the case of the Blacklegged Tick, both the larval and nymph stages, as well as the adult stages, do not have well-defined eyes like other tick species you might encounter. This characteristic is consistent across the species and is important for identifying them in the field, especially since many other ticks may have more obvious eye structures.

Understanding this trait can help in identifying different tick species, which is crucial for public health and awareness, as different ticks can carry various diseases. The fact that the other options mention specific life stages of other tick species, which may have differing ocular features, further clarifies why they do not apply to this question.