INSTRUCTION: Read the following text to answer the question.

INSTRUCTION: Read the following text to answer the question.

Abstract

Rare diseases are diseases that affect fewer than 1 in 2,000 people. Due to their rarity, it can be extremely challenging for doctors to diagnose these diseases in their patients — it often takes 6 – 8 years for some patients to get a diagnosis. Even though they are uncommon, rare diseases still have a significant impact on families and communities and need greater attention. Fatal familial insomnia (FFI) is a rare disease that affects the brain and gradually reduces a person’s ability to sleep. FFI gets worse over time and causes severe complications. There is currently no cure for FFI, so more research is crucial — not only for understanding FFI but also for unlocking potential treatments for other rare diseases. Rare disease research brings hope for a better future to those living with FFI and other rare conditions.

Available at: https://kids.frontiersin.org/articles/10.3389/frym.2025.1523273. Accessed on: Aug 2nd, 2025.

As used in the abstract, what is the best definition for the word diagnose?