Final answer:
Kenisha, the death investigator, would indicate in her report that the decedent was found in a prone position, which refers to laying face-down on the stomach.
Step-by-step explanation:
The main answer to the question regarding the decedent's position is A. Prone. When someone is found lying on their stomach facing downwards, they are said to be in a prone position. This term is an important piece of vocabulary for professionals like forensic anthropologists and medical examiners during the assessment of a death scene. In contrast, a supine position refers to a person lying on their back facing upwards, which is not the case here. Kenisha would document in her report that the decedent was found in a prone position. This correct identification of the body position may assist in the later stages of investigation, potentially affecting the determination of cause and manner of death.