Read the following excerpt, then answer the following question. "allergies may seem similar to a cold, but the causes are very different. an allergy occurs when the body's immune system reacts to something the body comes in contact with. how can you know if you have a cold or allergies? a short-term illness caused by contact with a virus is a cold. allergies can't be spread from person to person and may last longer than a cold. neither allergies nor a cold are fun to experience, but understanding the differences can you know how to respond." which format does the author use to the reader understand the main idea? a. problem/solution b. cause/effect c. comparison/contrast d. sequential/chronological order