Alex says that the tree root tripped him because it is mean. This is an example of

A. Letter size becomes bigger and more even with age: Actually, handwriting tends to become smaller, neater, and more uniform with age due to improved fine motor control, so this statement is incorrect.
B. Boys usually outperform girls in fine motor skills: The typical finding is the opposite; girls generally outperform boys on many fine-motor tasks in middle/late childhood.
C. Increased myelination affects the development of gross motor skills but not fine motor skills: Myelination improves speed and coordination for both gross and fine motor skills; it’s not limited to gross motor development.
D. Girls usually outperform boys in fine motor skills: Girls typically show earlier and/or better performance on fine motor tasks (handwriting, manual dexterity) during middle and late childhood.

A. higher and lower brain functions: Brain death is defined as the irreversible cessation of all functions of the entire brain, including higher cortical activity and brainstem (lower) functions; this “whole-brain” criterion is what most physicians use.
B. the heartbeat: Loss of the heartbeat is circulatory or cardiac death; with mechanical ventilation and support the heart can continue beating even when the brain has irreversibly ceased functioning, so this is not the defining feature of brain death.
C. the higher cortical functions of the brain: Loss of cortical function alone (e.g., no consciousness) may produce a persistent vegetative state, but brainstem functions can remain; that situation is not equivalent to whole-brain death.
D. lower brainstem functions: Loss of brainstem function (respiratory drive, brainstem reflexes) is critical and may define brainstem death in some places, but the widely used medical definition is cessation of all brain functions (both cortical and brainstem), so lower-brainstem cessation alone doesn’t capture the full standard.