As penny read a book about horses, she applied the information to her experience at her uncle’s farm last summer. this is an example of

elaboration

Explanation:

Elaboration refers to the process of adding more information about a subject. Adding more details gives extra information which helps the reader to have deep knowledge about the subject. The main purpose of giving elaboration is to make the topic more clear to the reader. In the above case, Penny adds additional information about the horses after reading the book on the horses.

a. "to practice" is the best phrase to complete the sentence.

explanation:

during the summer, she likes to practice her soccer skills so that she is ready to play in the fall.

(note that : all the other options "the practicing of", "practice for" and "to do a practice on" are inappropriate as they make the sentence grammatically incorrect.)

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