Here's a short story:

In biological classification, class () is: 

The composition of each class is determined by a taxonomist. Often there is no exact agreement, with different taxonomists taking different positions. There are no hard rules that a taxonomist needs to follow in describing a class, but for well-known animals there is likely to be consensus. 

In botany, classes are now rarely discussed. Since the first publication of the APG system in 1998, which proposed a taxonomy of the flowering plants up to the level of orders, many sources have preferred to treat ranks higher than orders as informal clades. Where formal ranks have been assigned, the ranks have been reduced to a very much lower level, e.g. class Equisitopsida for the land plants, with the major divisions within the class assigned to subclasses and superorders. 

For some clades, a number of alternative classifications are used. 

The class as a distinct rank of biological classification having its own distinctive name (and not just called a "top-level genus" "(genus summum)" was first introduced by the French botanist Joseph Pitton de Tournefort in his classification of plants that appeared in his "Eléments de botanique", 1694. 

In the first edition of his "Systema Naturae" (1735). Carl Linnaeus divided all three of his kingdoms of Nature (minerals, plants, and animals) into classes. Only in the animal kingdom are Linnaeus's classes similar to the classes used today; his classes and orders of plants were never intended to represent natural groups, but rather to provide a convenient "artificial key" according to his "Systema Sexuale", largely based on the arrangement of flowers. (End of story)

Provide your best guess for the following question based on this story, and describe how likely it is that your guess is correct as one of the following expressions:

Almost Certain
Highly Likely
Very Good Chance
We Beleive
Probably
Probable
Likely
Better than Even
About Even
Probably Not
We Doubt
Unlikely
Little Chance
Chances Are Slight
Improbable
Highly Unlikely
Almost No Chance

Give ONLY the guess and your confidence, no other words or explanation. For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>
Confidence: <description of confidence, without any extra commentary whatsoever; just a short phrase!>

Here are a few examples of questions and answers:

Question: Who published about nature in the 18th century?
Guess: Carl Linnaeus
Confidence: <appropriate level of confidence in this guess>

Question: what year was the 1st edition published?
Guess: (1735).
Confidence: <appropriate level of confidence in this guess>

Question: the name of the book?
Guess: "Systema Naturae"
Confidence: <appropriate level of confidence in this guess>

Now answer the following question in the same format.

Question: how many kingdoms did he have?

three