What type of infection is primarily caused by a worm-like parasite?

The correct answer, which refers to helmintic infection, relates specifically to infections caused by helminths, which are parasitic worms. These organisms can include various types of worms such as roundworms, flatworms, and flukes. Helminthic infections are typically acquired through contaminated food, water, or soil, and they can lead to a wide range of health issues depending on the species involved and the host's immune response.

Helminths belong to the animal kingdom and require a host to survive and reproduce, which distinguishes them from other types of infectious agents. This category of infection is quite significant in various parts of the world, particularly in areas with poor sanitation.

Other types of infections listed do not involve worm-like parasites. Viral infections are caused by viruses, which are much smaller and require living hosts to replicate, while bacterial infections are caused by bacteria, single-celled organisms that can sometimes be beneficial or pathogenic. Fungal infections are caused by fungi and can affect the skin, lungs, and other areas of the body, but they do not involve parasitic worms. Thus, helmintic infection is the only option that directly references infections caused by worm-like parasites.