Which one of the following words ending in -est is spelled correctly A sillyest B bigest C sweettest D flattest?

Here's why:

* Superlative Adjectives: Words ending in "-est" are usually superlative adjectives, meaning they describe the highest degree of something.

* Spelling Rule: Superlative adjectives often follow a simple rule: add "-est" to the base adjective.

Let's look at the other options:

* A) sillyest: The correct superlative is "silliest."

* B) bigest: The correct superlative is "biggest."

* C) sweettest: The correct superlative is "sweetest."