Question

select the three adjectives. dont select any articles (a, an, or the). charles kuen kao won the nobel prize in physics in 2009 for groundbreaking work on fiber - optic cables, which use thin threads of glass or plastic to carry information in the form of light.

Explanation:

An adjective is a word that describes a noun. In the sentence, "groundbreaking" describes the work (a noun), "thin" describes the threads (a noun), and "fib - optic" describes the cables (a noun). Articles (a, an, the) are not adjectives in this context.

Answer:

groundbreaking, thin, fib - optic