Read the sentence. leonie jogged through the cool morning mist. what type of pronoun should the writer replace leonie with? objective reciprocal reflexive subjective

You would replace Leonie with a subjective pronoun because Leonie is the SUBJECT of the sentence.  How do we know that Leonie is the subject of the sentence?  Leonie is the one doing the main action (jogged, in this case). The subjective pronouns are I, you, and he/she/it when the subject is singular. For plural subjects the subjective pronouns are we, you (all), and they.  Collectively, these subjective pronouns are also called the personal pronouns.  Assuming Leonie is female (sorry, haven't heard that name before:), the correct pronoun would be she because she jogged.