Which of the following is the lowest category of classification?

1. Analyze the question The question asks for the lowest category in the hierarchy of biological classification (taxonomy).

2. Explain the concept Living things are grouped from the broadest category to the most specific one:

Kingdom → Phylum (Division in plants) → Class → Order → Family → Genus → Species

• The kingdom is the largest group and has the most diverse members.
• Each step down groups organisms that share more and more characteristics.
• The species is the smallest and most specific group. Its members can interbreed and produce fertile offspring.

3. Step-by-step solution

• A. Class is a high-level category, just below phylum. It is too broad.
• B. Species is the last rung of the ladder, so it is the lowest.
• C. Family sits above genus, so it is higher.
• D. Genus sits directly above species, so it is higher than species.

Ranking the options from highest to lowest: Class → Family → Genus → Species.

4. Answer The lowest category is the species, which is option B.

5. Exam tip Use this mnemonic for the order from the top: "King Philip Came Over For Good Soup" (Kingdom, Phylum, Class, Order, Family, Genus, Species). The last word, "Soup", is species, the lowest. Also remember that a scientific name is written as Genus species (e.g., Homo sapiens), with the species name coming last.