[Solved] At what age do infants begin forming basic level categories? A) 2 months B) 3-4 months C) 6-7 months D) 1 year Microscopic Composition: The arrangement and structure of cells and tissues as seen under a microscope, revealing details not observable to the naked eye. Tissues: Collections of similar cells and their extracellular matrix from the same origin that carry out a specific function. Atypical Nevus: A mole that appears unusual or different from common moles, sometimes posing a higher risk of melanoma. Trunk: The main part of the human body that extends from the neck to the abdomen, excluding the head, arms, and legs.