The correct hierarchical arrangement of taxonomic categories in descending order for animals is Kingdom, Phylum, Class, Order, Family, Genus, Species.

Here are the solutions to the questions:

1. The correct hierarchical arrangement of taxonomic categories in descending order for animals is Kingdom, Phylum, Class, Order, Family, Genus, Species.

   • The correct option is (a).

   • a) Kingdom, Phylum, Class, Order, Family, Genus, Species

2. According to the rules of binomial nomenclature, the scientific name should be italicized, with the genus name capitalized and the species epithet in lowercase. The author's name is often abbreviated.

   • The correct option is (a).

   • a) Mangifera indica Linn.

3. Biological names are typically in Latin or Latinized, not "any language."

   • The correct option is (a).

   • a) Biological names can be written in any language

4. The most conclusive criterion for two organisms belonging to the same species is their ability to interbreed and produce fertile offspring. In plants, this is indicated by the formation of seeds after reproduction.

   • The correct option is (b).

   • b) Can reproduce freely with each other and form seeds

5. ICBN stands for International Code of Botanical Nomenclature.

   • The correct option is (c).

   • c) International Code of Botanical Nomenclature